Mouse Wheel Camera

Maybe you should rethink it a bit... use MouseZ() to control the SPEED of the movement then you simply have to call this:

If MouseZ() > 0 Then Movementz = MouseZ()
If MouseZ() < 0 then movementz = MouseZ()

You know... use it like an accelerator pedal.

But then again I really can't see what you are doing... It might be brilliant... Good luck.
-RZ