Hi
I’m messing around with Texture Paint and I found something that confuses me.
In my textscene I have an Object in combination with the “Bool Tool”.
I added 2 UV-Maps to the Object. But if I rename the UV-Map then Blender seems to ignore it.
It only works if I use names like “UVMap” oder “UVMap.001”, “UVMap.002” and so on.
See here:
Is this a bug or a feature ? 
Kind regards
Alain
Just like with materials, it also combines UV maps between the cutter and the target. Add the same UV map to the cutter object.
It’s an user error until such time the user posts a test file, instead of expecting others to waste their time setting it up when you already have it. Bug reporting instructions tell to share a file and test on multiple systems. It also asks basic information such as Blender version, which you’ve hidden by cropping it out, and is relevant when others try on their systems.
Sorry, I did not think about uploading the File, how stupid of me 
Here it is:
UV-Mapping_packed.blend (1.3 MB)
Blender 2.79, Windows 7.
This does seem like odd behaviour. I’ve never used multiple UV maps, but playing around with your example file, I couldn’t figure it out either. I can’t say whether it’s a bug or that there’s some detail that’s been missed.
Perhaps now that the file is posted, JA12 could enlighten us both. The info already supplied by this entity… well, I’m not sure what he’s talking about.
Post a bug report.
I can replicate the issue with the names. Simpler to test if the UV map name is changed for the cutter. When combined, it puts that map as first, it always adds to the UV map list, and one of them will have a useless layout with all UV’s at 0,0.