I get a screenspace problem, or what should I call it. Small mouse or wacompen movements give big translations/rotations/scales, collisions take place far away from surfaces, or don't occur at all. I have a dual monitor setup, could it be the plugin is mapping both monitors as one screen? Or is it a Wacom problem?
Do you use some custom layout? Can you share it?
Im also on dual screen, 30" + 27" + wacom, tried all built-in layouts, works okay
I have a 24HD Cintiq as primary and a 24" + Wacom as secondary, on a GTX 460.
I'll try and switch around a bit to see if that changes anything.
 Partially fixed: I switched the monitorcables around to a more standard setup (my 2nd input was set to primary) and now translate and rotate respond normally. Although I don't get any response on 'scale'. Everything else works, strange.
Is it intentional that any selected objects are ignored by the plugin? This confuses me, I would expect the logic to be inverse - select what you want to be affected (and if you don't select anything affect everything)