Use ordinal of parts/items as the default meta, allows for holes in the setup but lets default configs be consistent regardless of other mods.

core/AEConfig.java

@@ -236,20 +236,40 @@ public class AEConfig extends Configuration implements IConfigureableObject, ICo
 			super.save();
 	}
 
-	public int getFreeMaterial()
+	public int getFreeIDSLot(int varID, String Category)
 	{
+		boolean alreadyUsed = false;
 		int min = 0;
-		for (Property p : getCategory( "materials" ).getValues().values())
+
-			min = Math.max( min, p.getInt() + 1 );
+		for (Property p : getCategory( Category ).getValues().values())
-		return min;
+		{
+			int thisInt = p.getInt();
+
+			if ( varID == thisInt )
+				alreadyUsed = true;
+
+			min = Math.max( min, thisInt + 1 );
+		}
+
+		if ( alreadyUsed )
+		{
+			if ( min < 1000 )
+				min = 1000;
+
+			return min;
+		}
+
+		return varID;
 	}
 
-	public int getFreePart()
+	public int getFreeMaterial(int varID)
 	{
-		int min = 0;
+		return getFreeIDSLot( varID, "materials" );
-		for (Property p : getCategory( "parts" ).getValues().values())
+	}
-			min = Math.max( min, p.getInt() + 1 );
+
-		return min;
+	public int getFreePart(int varID)
+	{
+		return getFreeIDSLot( varID, "parts" );
 	}
 
 	@Override

items/materials/ItemMaterial.java

@@ -136,7 +136,7 @@ public class ItemMaterial extends AEBaseItem implements IStorageComponent, IUpgr
 
 			if ( enabled )
 			{
-				int newMaterialNum = AEConfig.instance.get( "materials", name, AEConfig.instance.getFreeMaterial() ).getInt();
+				int newMaterialNum = AEConfig.instance.get( "materials", name, AEConfig.instance.getFreeMaterial( mat.ordinal() ) ).getInt();
 				mat.damageValue = newMaterialNum;
 				ItemStackSrc output = new ItemStackSrc( this, newMaterialNum );
 

items/parts/ItemPart.java

@@ -80,7 +80,7 @@ public class ItemPart extends AEBaseItem implements IPartItem, IItemGroup
 
 		if ( enabled )
 		{
-			int newPartNum = AEConfig.instance.get( "parts", name, AEConfig.instance.getFreePart() ).getInt();
+			int newPartNum = AEConfig.instance.get( "parts", name, AEConfig.instance.getFreePart( varID ) ).getInt();
 			ItemStackSrc output = new ItemStackSrc( this, newPartNum );
 
 			PartTypeIst pti = new PartTypeIst();