I see the same problem in Rhino with my Wacom pen.
But no solution so far. I will poke around, but if anyone has some suggestions how to fix that, please share.
Hi
I always have the same problem with R6 which is more a bug than a 3d software at this time.
First solution is to work with R5 instead or load wacom backup user preferences, this has solved
temporarily the right clic bug.