This might be the issue where the mouse is weirdly flickering on the side and the click was just consumed entirely without any effect on the game. Had it happen to one of my friends when he playtested the game. Not sure what's causing it but after he updated his graphic drivers it worked. read on a forum that it happens on older hardware with my ue4 version. Sorry about this, I will try to resolve this once the uploads unlock after the jam!