"Drive surfaces" are what mastercam will calculate the toolpath to.
Use the other surfaces as "Check Surfaces" , to force mastercam to stay away from
A surface selected for "dive" cannot also be a "check"
HINT---the more entities that are selected, the longer it takes to calculate a path, keep it simple, and add entities as you go, don't blindly add all the others that weren't selected as "drive"
Containment boundaries are used to keep the tool in a particular area, rotary work sometimes may use a boundary on the ends to stop the tool going too far ( ie into the chuck jaws, or falling off the end )