Ctrl+ R removes my mask and ctrl+1-5 doesn't activate my subdivision. Any idea what I'm doing wrong?
Ctrl R works for mask in Sculpt Mode but for Ctrl 1 - 5 to work to add a subdivision surface you need to be in Object Mode.
Are you perhaps using Emulate Numpad? Then the Subdivision shortcut won't work (neither will anything else using 'normal', non-Numpad numbers).