Hey Erika, good point. I guess you are right since I'm using a Mac. I'm just trying to figure out how to get rid of these files since I can't actually see them...
Since it looks a bit complicated to remove these files, and I think Mac will always creates these little bastards whenever I duplicate a folder, isn't it possible to tell Spine to ignore these files? I don't know, in the next release maybe... just "ignore "._" files? Thanks a lot for your help, I'll try to remove the files!
By the way it looks like the Format version of the disk (ExFat or Mac OS Extended) has a role in the creations of these "._" files...