03-28-2022, 12:21 PM
Going back to the beginning 
When something like that occurs, reduce to the simplest image.
Go to the top of the layer stack, make a Layer > New-from-visible
Drag that layer (Visible) into the toolbox to open as a new single layer image.
Does that look like your required icon ?
Export that as a Windows .icon
Does that look as expected ? If not, how are you viewing the .icon
Quote:...I have merged several layers into one layer, and I'm simply choosing that single, merged layer to export. (Not even trying to do the multi-size thing.)
When something like that occurs, reduce to the simplest image.
Go to the top of the layer stack, make a Layer > New-from-visible
Drag that layer (Visible) into the toolbox to open as a new single layer image.
Does that look like your required icon ?
Export that as a Windows .icon
Does that look as expected ? If not, how are you viewing the .icon