RhinoCAM does not currently do turning, only milling. I have no idea if or when they will integrate that into the plug-in.
As far as Tabs go, they are not in the current implementation of RhinoCAM 1.0, they will be in Visual Mill 6 (now in Beta), which will become RhinoCAM 2.0. As to when the release version of either will appear, again, no idea... RhinoCAM will be after VM, so I don't expect it anytime soon.
Pointcloud was recommending you visit the MecSoft user forum, it's at
http://www.mecsoft.com/phpbb/ --ch