Thanks for trying!
Im on W10 and im not having any issues. It shouldn't even show up borderless if you didn't switch the settings. If you changed any window sizes manually, but still got the "fullscreen" option in the settings, it might reapply that at some point. Its weird you cant touch anything though. Does this happen again after restarting the game?
What exactly do you mean by weirdness concerning walls/doors in front of goblins? Theres some cases where they clip into things, or the wall transparency is not optimal, if thats what you mean.