diff --git a/src/mrtjp/mcframes/api/IFrame.java b/src/mrtjp/mcframes/api/IFrame.java
index cf7ddb1..5ac17db 100755
--- a/src/mrtjp/mcframes/api/IFrame.java
+++ b/src/mrtjp/mcframes/api/IFrame.java
@@ -27,14 +27,14 @@ public interface IFrame
      * @param x The x coordinate.
      * @param y The y coordinate.
      * @param z The z coordinate.
-     * @param side The side of the block, as a ForgeDirection
-     * @return True if the side can stick on to another block.
+     * @param side The side of this block, as a ForgeDirection
+     * @return True if the side can grab another block.
      */
     boolean stickOut(World w, int x, int y, int z, int side);
 
     /**
      * Used to check if this frame block can be grabbed on the
-     * given side from another frame.
+     * given side by another frame.
      *
      * Convention requires that this method yields the same result
      * on both client and server.
@@ -43,8 +43,8 @@ public interface IFrame
      * @param x The x coordinate.
      * @param y The y coordinate.
      * @param z The z coordinate.
-     * @param side The side of the block, as a ForgeDirection
-     * @return True if the side can be stuck onto by a frame block.
+     * @param side The side of this block, as a ForgeDirection
+     * @return True if the side can be grabbed by a frame block.
      */
     boolean stickIn(World w, int x, int y, int z, int side);
 }
\ No newline at end of file
diff --git a/src/mrtjp/mcframes/motor.scala b/src/mrtjp/mcframes/motor.scala
index 62120ce..7f3b5ae 100755
--- a/src/mrtjp/mcframes/motor.scala
+++ b/src/mrtjp/mcframes/motor.scala
@@ -125,6 +125,7 @@ class TileMotor extends InstancedBlockTile with TTileOrient with IFrame
                 r.push()
                 r.setWorld(world)
                 r.setDirection(getMoveDir)
+                r.setSpeed(1/16D)
                 r.addBlocks(blocks)
                 r.execute()
                 r.pop()
diff --git a/src/mrtjp/relocation/api/IMovementCallback.java b/src/mrtjp/relocation/api/IMovementCallback.java
new file mode 100644
index 0000000..f53bd77
--- /dev/null
+++ b/src/mrtjp/relocation/api/IMovementCallback.java
@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2015.
+ * Created by MrTJP.
+ * All rights reserved.
+ */
+package mrtjp.relocation.api;
+
+/**
+ * Interface that can be used by things that wish to receive events for
+ * a move that they executed.  This interface is passed into the {@link Relocator}
+ * during movement construction.
+ *
+ * For example, a motor may wish to know when the movement completes.  In which case,
+ * the motor tile itself would implement this interface and pass itself into the
+ * Relocator.
+ *
+ * These methods are only called server-side.  Clients will not receive any of
+ * these events, as this class is registered during the execution of a move, which
+ * can only happen server-side.
+ *
+ */
+public interface IMovementCallback
+{
+    /**
+     * Called once move starts.  The descriptor contains methods that
+     * describe the state of the current movement that this callback
+     * was registered to.
+     *
+     * This descriptor is properly weak-referenced, keep or discard it
+     * at your own leasure.
+     *
+     * @param desc The movement descriptor for the current move.
+     */
+    void setDescriptor(IMovementDescriptor desc);
+
+    /**
+     * Called when the movement starts, when the animation starts playing.
+     */
+    void onMovementStarted();
+
+    /**
+     * Called when the movement completes, and all blocks have moved over.
+     */
+    void onMovementFinished();
+}
\ No newline at end of file
diff --git a/src/mrtjp/relocation/api/IMovementDescriptor.java b/src/mrtjp/relocation/api/IMovementDescriptor.java
new file mode 100644
index 0000000..134af8a
--- /dev/null
+++ b/src/mrtjp/relocation/api/IMovementDescriptor.java
@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) 2015.
+ * Created by MrTJP.
+ * All rights reserved.
+ */
+package mrtjp.relocation.api;
+
+/**
+ * This is the interface of the object that is given to an {@link IMovementCallback} so
+ * it may access movement information whenever it needs to during the movement.
+ *
+ * Results of all methods is only valid during movement, undefined otherwise.  Use
+ * isMoving() to check before using any values from this.
+ */
+public interface IMovementDescriptor
+{
+    /**
+     * @return True if the structure is moving.
+     */
+    boolean isMoving();
+
+    /**
+     * @return The progress of the movement scaled between 0 and 1.
+     */
+    double getProgress();
+
+    /**
+     * @return The size of the moving structure, zero if it is no longer moving.
+     */
+    int getSize();
+}
\ No newline at end of file
diff --git a/src/mrtjp/relocation/api/Relocator.java b/src/mrtjp/relocation/api/Relocator.java
index 09e3ccf..d8c7126 100755
--- a/src/mrtjp/relocation/api/Relocator.java
+++ b/src/mrtjp/relocation/api/Relocator.java
@@ -16,10 +16,8 @@ import java.util.Set;
 public abstract class Relocator
 {
     /**
-     * Pushes the instance of the Relocator onto the stack.
+     * Pushes an instance of the Relocator onto the stack.
      * Must be called before using any methods.
-     *
-     * @throws IllegalStateException If the Relocator is already on the stack.
      */
     public abstract void push();
 
@@ -27,7 +25,7 @@ public abstract class Relocator
      * Pops the instance of the Relocator off the stack.
      * Must be called after you are done using this.
      *
-     * @throws IllegalStateException If the Relocator is not on the stack.
+     * @throws IllegalStateException If there is no Relocator on the stack.
      */
     public abstract void pop();
 
@@ -35,6 +33,7 @@ public abstract class Relocator
      * Sets the world for the movement.
      *
      * @param world The world in which the movement will occure.
+     * @throws IllegalStateException If the world was already set.
      */
     public abstract void setWorld(World world);
 
@@ -45,9 +44,32 @@ public abstract class Relocator
      * @param dir The direction to move the blocks.
      *
      * @throws IllegalStateException If the Relocator is not on the stack.
+     * @throws IllegalStateException If the direction was already set.
      */
     public abstract void setDirection(int dir);
 
+    /**
+     * Sets the speed of the movement. Must be greater than 0 and
+     * less than 1.
+     *
+     * @param speed The speed of the movement, in meters/tick.
+     *
+     * @throws IllegalStateException If the Relocator is not on the stack.
+     * @throws IllegalStateException If the speed was already set.
+     */
+    public abstract void setSpeed(double speed);
+
+    /**
+     * Sets a callback object that receives events during the actual move.
+     * This is optional and is not required to be set.
+     *
+     * @param callback The callback to register for this move.
+     *
+     * @throws IllegalStateException If the Relocator is not on the stack.
+     * @throws IllegalStateException If a callback was already set.
+     */
+    public abstract void setCallback(IMovementCallback callback);
+
     /**
      * Following methods are used to add blocks to the queue.
      *
@@ -64,6 +86,8 @@ public abstract class Relocator
      * @return True if the movement was successfully started.
      *
      * @throws IllegalStateException If the Relocator is not on the stack.
+     * @throws IllegalStateException If any of the required parameters are not set
+     *                               or are invalid.
      */
     public abstract boolean execute();
 }
\ No newline at end of file
diff --git a/src/mrtjp/relocation/blocks.scala b/src/mrtjp/relocation/blocks.scala
index 8f0f9f7..ab01a63 100755
--- a/src/mrtjp/relocation/blocks.scala
+++ b/src/mrtjp/relocation/blocks.scala
@@ -18,7 +18,7 @@ import net.minecraft.world.World
 
 import scala.collection.JavaConversions._
 
-class BlockMovingRow extends InstancedBlock("relocation.BlockMovingRow", Material.iron)
+class BlockMovingRow extends InstancedBlock("relocation.blockmovingrow", Material.iron)
 {
     setHardness(-1F)
     setStepSound(Block.soundTypeGravel)
@@ -33,10 +33,14 @@ object TileMovingRow
         w.setBlock(r.pos.x, r.pos.y, r.pos.z, RelocationMod.blockMovingRow, 0, 3)
     }
 
-    def getBoxFor(w:World, r:BlockRow, progress:Double) =
+    def getBoxFor(w:World, r:BlockRow, progress:Double):Cuboid6 =
     {
         val p = r.pos.copy.offset(r.moveDir^1)
-        w.getBlock(p.x, p.y, p.z).getCollisionBoundingBoxFromPool(w, p.x, p.y, p.z) match
+        val bl = w.getBlock(p.x, p.y, p.z)
+
+        if (bl == RelocationMod.blockMovingRow) return Cuboid6.full.copy()
+
+        bl.getCollisionBoundingBoxFromPool(w, p.x, p.y, p.z) match
         {
             case aabb:AxisAlignedBB => new Cuboid6(aabb).sub(new Vector3(r.pos))
                     .add(new Vector3(BlockCoord.sideOffsets(r.moveDir))*progress)
diff --git a/src/mrtjp/relocation/events.scala b/src/mrtjp/relocation/events.scala
index 9210ea6..c8ad494 100755
--- a/src/mrtjp/relocation/events.scala
+++ b/src/mrtjp/relocation/events.scala
@@ -17,6 +17,7 @@ object RelocationEventHandler
     def worldUnload(event:WorldEvent.Unload)
     {
         RelocationSPH.onWorldUnload(event.world)
+        MovementManager2.onWorldUnload(event.world)
     }
 
     @SubscribeEvent
@@ -40,13 +41,6 @@ object RelocationEventHandler
             MovementManager2.onTick(false)
         }
     }
-
-    @SubscribeEvent
-    def clientTick(event:TickEvent.ClientTickEvent)
-    {
-        if (event.phase == TickEvent.Phase.END)
-            MovementManager2.onTick(true)
-    }
 }
 
 object RelocationClientEventHandler
@@ -64,4 +58,11 @@ object RelocationClientEventHandler
     {
         MovingRenderer.onRenderWorldEvent()
     }
+
+    @SubscribeEvent
+    def clientTick(event:TickEvent.ClientTickEvent)
+    {
+        if (event.phase == TickEvent.Phase.END)
+            MovementManager2.onTick(true)
+    }
 }
\ No newline at end of file
diff --git a/src/mrtjp/relocation/handler/RelocationAPI_Impl.scala b/src/mrtjp/relocation/handler/RelocationAPI_Impl.scala
index 8e1df2e..305939c 100755
--- a/src/mrtjp/relocation/handler/RelocationAPI_Impl.scala
+++ b/src/mrtjp/relocation/handler/RelocationAPI_Impl.scala
@@ -5,16 +5,10 @@
  */
 package mrtjp.relocation.handler
 
-import java.util.{Set => JSet}
-
-import codechicken.lib.vec.BlockCoord
-import mrtjp.relocation.api.{BlockPos, ITileMover, RelocationAPI, Relocator}
+import mrtjp.relocation.api.{ITileMover, RelocationAPI}
 import mrtjp.relocation.{MovementManager2, MovingTileRegistry}
 import net.minecraft.world.World
 
-import scala.collection.JavaConversions._
-import scala.collection.mutable.{Set => MSet}
-
 object RelocationAPI_Impl extends RelocationAPI
 {
     var isPreInit = true
@@ -41,73 +35,4 @@ object RelocationAPI_Impl extends RelocationAPI
 
     override def isMoving(world:World, x:Int, y:Int, z:Int) =
         MovementManager2.isMoving(world, x, y, z)
-}
-
-object Relocator_Impl extends Relocator
-{
-    private var enabled = false
-
-    private var world:World = null
-    private var dir = -1
-    private val blocks = MSet[BlockCoord]()
-
-    private def assertState()
-    {
-        if (!enabled) throw new IllegalStateException("Relocator must be on the stack before use.")
-    }
-
-    override def push()
-    {
-        if (enabled) throw new IllegalStateException("Relocator is already on the stack.")
-        enabled = true
-    }
-
-    override def pop()
-    {
-        if (!enabled) throw new IllegalStateException("Relocator is not on the stack.")
-        enabled = false
-        world = null
-        dir = -1
-        blocks.clear()
-    }
-
-    override def setWorld(w:World)
-    {
-        assertState()
-        if (world != null) throw new IllegalStateException("World already set.")
-        world = w
-    }
-
-    override def setDirection(d:Int)
-    {
-        assertState()
-        if (dir != -1) throw new IllegalStateException("Direction already set.")
-        dir = d
-    }
-
-    override def addBlock(x:Int, y:Int, z:Int)
-    {
-        assertState()
-        blocks += new BlockCoord(x, y, z)
-    }
-
-    override def addBlock(bc:BlockPos)
-    {
-        addBlock(bc.x, bc.y, bc.z)
-    }
-
-    override def addBlocks(blocks:JSet[BlockPos])
-    {
-        for (b <- blocks) addBlock(b)
-    }
-
-    override def execute() =
-    {
-        assertState()
-        if (world == null)  throw new IllegalStateException("World must be set before move.")
-        if (world.isRemote) throw new IllegalStateException("Movements cannot be executed client-side.")
-        if (dir == -1)      throw new IllegalStateException("Direction must be set before move.")
-        if (blocks.isEmpty) throw new IllegalStateException("At least 1 block is required for move.")
-        MovementManager2.tryStartMove(world, blocks.toSet, dir)
-    }
 }
\ No newline at end of file
diff --git a/src/mrtjp/relocation/handler/Relocator_Impl.scala b/src/mrtjp/relocation/handler/Relocator_Impl.scala
new file mode 100644
index 0000000..33aa4d4
--- /dev/null
+++ b/src/mrtjp/relocation/handler/Relocator_Impl.scala
@@ -0,0 +1,121 @@
+/*
+ * Copyright (c) 2015.
+ * Created by MrTJP.
+ * All rights reserved.
+ */
+package mrtjp.relocation.handler
+
+import java.util.{Set => JSet}
+
+import codechicken.lib.vec.BlockCoord
+import mrtjp.relocation.MovementManager2
+import mrtjp.relocation.api.{IMovementCallback, BlockPos, Relocator}
+import net.minecraft.world.World
+
+import scala.collection.JavaConversions._
+import scala.collection.mutable.{Set => MSet, Stack => MStack}
+
+class RelocationRun
+{
+    var world:World = null
+    var dir = -1
+    var speed = 0.0
+    var callback:IMovementCallback = null
+    val blocks = MSet[BlockCoord]()
+
+    def clear()
+    {
+        world = null
+        dir = -1
+        speed = 0
+        callback = null
+        blocks.clear()
+    }
+}
+
+object Relocator_Impl extends Relocator
+{
+    var mainStack = new MStack[RelocationRun]()
+    var tempStack = new MStack[RelocationRun]()
+
+    private def assertState()
+    {
+        if (mainStack.isEmpty) throw new IllegalStateException("Relocator stack is empty.")
+    }
+
+    override def push()
+    {
+        val r = if (tempStack.isEmpty) new RelocationRun else tempStack.pop()
+        mainStack.push(r)
+    }
+
+    override def pop()
+    {
+        assertState()
+        val r = mainStack.pop()
+        r.clear()
+        tempStack.push(r)
+    }
+
+    override def setWorld(world:World)
+    {
+        assertState()
+        val top = mainStack.top
+        if (top.world != null) throw new IllegalStateException("World already set.")
+        top.world = world
+    }
+
+    override def setDirection(dir:Int)
+    {
+        assertState()
+        val top = mainStack.top
+        if (top.dir != -1) throw new IllegalStateException("Direction already set.")
+        top.dir = dir
+    }
+
+    override def setSpeed(speed:Double)
+    {
+        assertState()
+        val top = mainStack.top
+        if (top.speed > 0) throw new IllegalStateException("Speed already set.")
+        top.speed = speed
+    }
+
+
+    override def setCallback(callback:IMovementCallback)
+    {
+        assertState()
+        val top = mainStack.top
+        if (top.callback != null) throw new IllegalStateException("Callback already set.")
+        top.callback = callback
+    }
+
+    override def addBlock(x:Int, y:Int, z:Int)
+    {
+        assertState()
+        mainStack.top.blocks += new BlockCoord(x, y, z)
+    }
+
+    override def addBlock(bc:BlockPos)
+    {
+        addBlock(bc.x, bc.y, bc.z)
+    }
+
+    override def addBlocks(blocks:JSet[BlockPos])
+    {
+        for (b <- blocks) addBlock(b)
+    }
+
+    override def execute() =
+    {
+        assertState()
+        val top = mainStack.top
+        if (top.world == null)  throw new IllegalStateException("World must be set before move.")
+        if (top.world.isRemote) throw new IllegalStateException("Movements cannot be executed client-side.")
+        if (top.dir == -1)      throw new IllegalStateException("Direction must be set before move.")
+        if (top.speed <= 0)     throw new IllegalStateException("Speed must be greater than 0.")
+        if (top.speed >= 1)     throw new IllegalStateException("Speed must be less than 1.")
+        if (top.blocks.isEmpty) throw new IllegalStateException("No blocks queued for move.")
+        MovementManager2.tryStartMove(top.world, top.blocks.toSet, top.dir, top.speed, top.callback)
+    }
+}
\ No newline at end of file
diff --git a/src/mrtjp/relocation/handler/network.scala b/src/mrtjp/relocation/handler/network.scala
index ee4b1fc..94a8561 100755
--- a/src/mrtjp/relocation/handler/network.scala
+++ b/src/mrtjp/relocation/handler/network.scala
@@ -84,7 +84,15 @@ object RelocationSPH extends RelocationPH with IServerPacketHandler
     def onWorldUnload(world:World)
     {
         if(!world.isRemote)
+        {
             updateMap.remove(world)
+            if (chunkWatchers.nonEmpty)
+            {
+                val players = getServerPlayers
+                for (p <- players) if (p.worldObj.provider.dimensionId == world.provider.dimensionId)
+                    chunkWatchers.remove(p.getEntityId)
+            }
+        }
     }
 
     def onChunkWatch(p:EntityPlayer, c:ChunkCoordIntPair)
diff --git a/src/mrtjp/relocation/movement.scala b/src/mrtjp/relocation/movement.scala
index 8284454..0e41041 100755
--- a/src/mrtjp/relocation/movement.scala
+++ b/src/mrtjp/relocation/movement.scala
@@ -10,12 +10,14 @@ import codechicken.lib.packet.PacketCustom
 import codechicken.lib.vec.BlockCoord
 import mrtjp.core.math.MathLib
 import mrtjp.core.world.WorldLib
-import mrtjp.relocation.handler.{RelocationSPH, RelocationConfig}
+import mrtjp.relocation.api.{IMovementCallback, IMovementDescriptor}
+import mrtjp.relocation.handler.{RelocationConfig, RelocationSPH}
 import net.minecraft.init.Blocks
 import net.minecraft.world.{ChunkCoordIntPair, World}
 import net.minecraftforge.common.DimensionManager
 
 import scala.collection.mutable.{HashMap => MHashMap, MultiMap => MMultiMap, Set => MSet}
+import scala.ref.WeakReference
 
 object MovementManager2
 {
@@ -48,6 +50,7 @@ object MovementManager2
             val struct = new BlockStruct
             struct.id = id
             struct.readDesc(in)
+            addStructToWorld(w, struct)
             id = in.readUShort()
         }
     }
@@ -58,8 +61,8 @@ object MovementManager2
             val struct = new BlockStruct
             struct.id = in.readUShort()
             struct.readDesc(in)
-            getWorldStructs(w).addStruct(struct)
-            for (b <- struct.allBlocks)
+            addStructToWorld(w, struct)
+            for (b <- struct.allBlocks) //rerender all moving blocks
                 w.func_147479_m(b.x, b.y, b.z)
         case 2 =>
             val id = in.readUShort()
@@ -88,10 +91,16 @@ object MovementManager2
 
     def isMoving(w:World, x:Int, y:Int, z:Int) = getWorldStructs(w).contains(x, y, z)
 
+    def addStructToWorld(w:World, b:BlockStruct)
+    {
+        getWorldStructs(w).addStruct(b)
+        b.onAdded(w)
+    }
+
     def getEnclosedStructure(w:World, x:Int, y:Int, z:Int) =
         getWorldStructs(w).structs.find(_.contains(x, y, z)).orNull
 
-    def tryStartMove(w:World, blocks:Set[BlockCoord], moveDir:Int):Boolean =
+    def tryStartMove(w:World, blocks:Set[BlockCoord], moveDir:Int, speed:Double, c:IMovementCallback):Boolean =
     {
         if (blocks.size > RelocationConfig.moveLimit) return false
 
@@ -117,8 +126,10 @@ object MovementManager2
 
         val struct = new BlockStruct
         struct.id = BlockStruct.claimID()
+        struct.speed = speed
         struct.rows = rows
-        getWorldStructs(w).addStruct(struct)
+        struct.callback = WeakReference(c)
+        addStructToWorld(w, struct)
         sendStruct(w, struct)
 
         true
@@ -156,9 +167,9 @@ object MovementManager2
 
     def cycleMove(w:World, struct:BlockStruct)
     {
-        for (r <- struct.rows) r.doMove(w)
-        for (r <- struct.rows) r.postMove(w)
-        for (r <- struct.rows) r.endMove(w)
+        struct.doMove(w)
+        struct.postMove(w)
+        struct.endMove(w)
 
         Utils.rescheduleTicks(w, struct.preMoveBlocks, struct.allBlocks, struct.moveDir)
 
@@ -184,8 +195,8 @@ class WorldStructs
 
     def removeFinished() =
     {
-        val finished = structs.filter(_.finished)
-        structs = structs.filterNot(_.finished)
+        val finished = structs.filter(_.isFinished)
+        structs = structs.filterNot(_.isFinished)
         finished
     }
 
@@ -213,12 +224,34 @@ object BlockStruct
     }
 }
 
+class MoveDesc(b:WeakReference[BlockStruct]) extends IMovementDescriptor
+{
+    def this(b:BlockStruct) = this(new WeakReference(b))
+
+    override def isMoving = b match {
+        case WeakReference(b:BlockStruct) => !b.isFinished
+        case _ => false
+    }
+
+    override def getProgress = b match {
+        case WeakReference(b:BlockStruct) => b.progress
+        case _ => -1
+    }
+
+    override def getSize = b match {
+        case WeakReference(b:BlockStruct) => b.allBlocks.size
+        case _ => 0
+    }
+}
+
 class BlockStruct
 {
     var id = -1
-    var progress = 0.0D
     var speed = 1/16D
     var rows:Set[BlockRow] = Set.empty
+    var callback = WeakReference[IMovementCallback](null)
+
+    var progress = 0.0D
 
     lazy val allBlocks = rows.flatMap(_.allBlocks)
     lazy val preMoveBlocks = rows.flatMap(_.preMoveBlocks)
@@ -228,8 +261,9 @@ class BlockStruct
 
     def contains(x:Int, y:Int, z:Int) = rows.exists(_.contains(x, y, z))
 
-    def push(){ progress = (progress+speed) min 1.0D }
-    def finished = progress >= 1.0D
+    def push(){ progress = math.min(1.0, progress+speed) }
+
+    def isFinished = progress >= 1.0D
 
     def getChunks:Set[ChunkCoordIntPair] =
     {
@@ -239,6 +273,37 @@ class BlockStruct
         c.result()
     }
 
+    def onAdded(w:World)
+    {
+        if (!w.isRemote) callback match
+        {
+            case WeakReference(c) =>
+                c.setDescriptor(new MoveDesc(this))
+                c.onMovementStarted()
+            case _ =>
+        }
+    }
+
+    def doMove(w:World)
+    {
+        for (r <- rows) r.doMove(w)
+    }
+
+    def postMove(w:World)
+    {
+        for (r <- rows) r.postMove(w)
+    }
+
+    def endMove(w:World)
+    {
+        for (r <- rows) r.endMove(w)
+        if (!w.isRemote) callback match
+        {
+            case WeakReference(c) => c.onMovementFinished()
+            case _ =>
+        }
+    }
+
     override def equals(obj:scala.Any) = obj match
     {
         case that:BlockStruct => id == that.id
@@ -280,6 +345,7 @@ class BlockRow(val pos:BlockCoord, val moveDir:Int, val size:Int)
         import MathLib.{basis, normal, shift}
 
         import math.{max, min}
+
         if (normal(x, y, z, moveDir) == normal(pos, moveDir))
         {
             val b1 = basis(pos, moveDir)