I've noticed this specifically in the SnagIt editor but suspect it works the same other places. The esc key on a Mac has an expected function - namely to exit full screen mode. Unfortunately it has some other action in SnagIt. This makes it more difficult to get out of full screen mode especially if one is used to other apps on a Mac ALL working! I extend the size of the screen by hand to nearly full screen to get max screen space without getting stuck in the position of not being able to get out of full screen with ease.