(12-23-2019, 01:55 PM)AmazingGimp Wrote: Ofnuts, I am using your Spinner.xcf actually. Where is this option to specify the ring layer as the layer to merge? During the interleave process?
Yes, it's in the interleave process, but you have to pick the right option. The dialog you show is for the "Stack of layers over current layers"(*), while the option you should use is "Single layer under stack":
(*) In that mode you would merge several input layers, so you don't specify a single layer but an image that contains the layers.