I don't have Mastercam but have run several Mastercam created programs on my cnc machine. I have been having some of my modeling and gcode done out side the shop and have just recently started using Madcam. I Have had Rhino for 3-4 years now but am just now beginning to pick up the needed knowledge to realise just how good it is.
Do you need automatic 4th axis cam? If not I can help you with the Rhino/Madcam package on doing your 4th axis till Joakim gets the 4th axis done. Since Madcam is a plugin to Rhino it is a painless process to manipulate the process and never have to close or open another program. I will not be at the pc much today, but ask away and anything I can do to help, is your's.
ps just so you know......I love the Rhino/Madcam package