[ploturo]

On the copies of the items you are using to replace the existing items, do you have multiple usesource elements?

You should only have your source listed on the replacement things, otherwise they will be active whenever any source from any of its usesource elements is active.

For example

<thing id="ExampleThing" replaces="OldThing">

     ...

     <usesource source="OldSource"/>
     <usesource source="NewSource"/>

</thing>

ExampleThing will replace OldThing whenever OldSource is active or NewSource is active.



If you remove the usesource element for OldSource, it will only replace OldThing when NewSource is active.

<thing id="ExampleThing" replaces="OldThing">

     ...

     <usesource source="NewSource"/>

</thing>

ExampleThing will only replace OldThing whenever NewSource is active.