I need to understand the request fully. Is this just a matter of turning on mouselook when the button is held down and turning off mouselook when it is released? In that case it is very easy to do. I will check in a version with that feature so you can test if that's good enough. (Wether or not it's enough, I think it will be useful on its own to have this.)
Yeah :), I was gonna tweak it myself last night, but didn't have time before the raid ;).
Basically being able to change my POV while hovering over the grid frames, rather than having to move my mouse off, hold down a key, change POV, then move back again.
//edit just tested it now, it works just like right clicking, however it does not work when I mouse over another frame, which is kinda the point :P