Götz,
167 images on the chair. I’m not sure what you mean with “a preview shot of the selection”.
There’s something else here which I’m told by someone much farther down the road in UE4 needs to be considered. According to him, “One of the issues with the tiny UV islands isn’t an issue for the texture but with the lightmap and baked lighting. When setting the object to static and using static lighting, those UVs can create incorrect or missing lighting if used in the second UV channel.”
I’ve not seen for myself what issues this causes in “the second UV channel”, much less why one needs a second UV channel, but not to jump into that just now. Would like to settle these issues first to simplify the conversation. I’m tasked with some work before I can run your proposed test, but can do.