I'm not fluent in script-fu (I code my scripts in Python, much easier/faster/powerful), but it looks like you are taking a reference to a layer and try to insert it in another image. This mean that this would be the same layer in both images...
You have to make an explicit copy of the layer, that you obtain with:
and then insert that layer into your destination image:
You have to make an explicit copy of the layer, that you obtain with:
Code:
(gimp-layer-new-from-drawable yourSourceLayer theImageWhereYouWantToInsertTheCopy)
Code:
(gimp-image-insert-layer theImageWhereYouWantToInsertTheCopy theLayerCopy parent position)