diff --git a/codechicken/lib/config/ConfigTag.java b/codechicken/lib/config/ConfigTag.java
index 82987d3..98472a4 100644
--- a/codechicken/lib/config/ConfigTag.java
+++ b/codechicken/lib/config/ConfigTag.java
@@ -200,10 +200,9 @@ public class ConfigTag extends ConfigTagParent
     {
         String vname;
         if(qualifiedname.contains(".") && bracequalifier.length() > 0)
-            vname = qualifiedname.substring(bracequalifier.length() + 1).replace(' ', '_');
+            vname = qualifiedname.substring(bracequalifier.length() + 1);
         else
             vname = qualifiedname;
-        vname.replace(' ', '_');
         
         if(newline && !first)
             ConfigFile.writeLine(writer, "", tabs);
@@ -220,7 +219,7 @@ public class ConfigTag extends ConfigTagParent
             if(value == null)
                 ConfigFile.writeLine(writer, vname, tabs);
             ConfigFile.writeLine(writer, "{", tabs);
-            saveTagTree(writer, tabs+1, qualifiedname.replace(' ', '_'));
+            saveTagTree(writer, tabs+1, qualifiedname);
             ConfigFile.writeLine(writer, "}", tabs);
         }
         else
diff --git a/codechicken/lib/config/ConfigTagParent.java b/codechicken/lib/config/ConfigTagParent.java
index f3ab8d7..0db27f9 100644
--- a/codechicken/lib/config/ConfigTagParent.java
+++ b/codechicken/lib/config/ConfigTagParent.java
@@ -117,7 +117,6 @@ public abstract class ConfigTagParent
 
     public ConfigTag getTag(String tagname, boolean create)
     {
-        tagname = tagname.replace('_', ' ');
         int dotpos = tagname.indexOf(".");
         String basetagname = dotpos == -1 ? tagname : tagname.substring(0, dotpos);
         ConfigTag basetag = childtags.get(basetagname);
@@ -149,7 +148,12 @@ public abstract class ConfigTagParent
         int dotpos = tagname.lastIndexOf(".");
         String lastpart = dotpos == -1 ? tagname : tagname.substring(dotpos+1, tagname.length());
         if(tag.parent != null)
-            return tag.parent.childtags.remove(lastpart) != null;
+        {
+            boolean ret = tag.parent.childtags.remove(lastpart) != null;
+            if(ret)
+                saveConfig();
+            return ret;
+        }
         
         return false;
     }
diff --git a/codechicken/lib/world/WorldExtensionManager.java b/codechicken/lib/world/WorldExtensionManager.java
index 95d5651..536a190 100644
--- a/codechicken/lib/world/WorldExtensionManager.java
+++ b/codechicken/lib/world/WorldExtensionManager.java
@@ -76,8 +76,9 @@ public class WorldExtensionManager
         @ForgeSubscribe
         public void onWorldSave(WorldEvent.Save event)
         {
-            for(WorldExtension extension : worldMap.get(event.world))
-                extension.save();
+            if(worldMap.containsKey(event.world))
+                for(WorldExtension extension : worldMap.get(event.world))
+                    extension.save();
         }
 
         @ForgeSubscribe