I do a simple profile operation to run a T-slot cutter on a part. The problem came when I tried to use a 0.03125″ narrow cutter to follow the curved surface at the bottom of the slot with multiple passes. I kept getting a spurious toolpath in the Advanced 3D Z-level operation. It would carve out the backside of the surface, but only on the lower half. I had better luck in SolidCAM using its surfacing Z-level, that is even included in the base package.
Webpage with SolidWorks assembly files:
Note the toolpaths will only appear in another demo BobCAD program, a paid-for version will not open the CAM part.