When you open Project Settings window and then go to collision, if you open up preset section and you don’t have a window large enough to fit everything in current window, window fails to create a scroll bar to allow us to scroll further down page, this includes inability to use scroll wheel to scroll down page:
http://puu.sh/gBziC/6ea290d8c9.png
To fix this issue at moment work around I noticed is that if you re-size window window realizes that it needs to provide a scroll bar:
http://puu.sh/gBzwR/54a87fa30f.png