Hi!
Just installed the Photoshop CC trial on my Mac to do some school stuff.
I need to use the Liquify tool in there, but oddly enough, both "zoom" keyboard shortcuts (Cmd + and Cmd -) zoom out on my Danish keyboard.
I tried switching the OS keyboard layout to US, and then it works. I notice, however, that on a US keyboard, the - sign is where the + one is on my Danish keyboard layout (and, I think, most of other European ones), so that might help fix the bug.
Cheers!