Hi, I posted here earlier, with the files and the logs attached there. Also some more pictures of the asset are there.
I solved most of that issue myself, however I still have a problem with the Ambient Occlusion.
Basically this happens. It's the back of the asset, so the player will probably never see it, but I still would like to know what the problem is so I can fix it in the future.
I tried all kinds of different baking presets, to no avail.