Cher: Oh, sorry! Stupid me. You said you were on Mac 🙂
Could it be as simple as some wrong setting in Wacom settings? It sounds like it is behaving like a mouse. I get this problem my self from time to time (I have a Cintiq and I’m on Mac) – and then I need to turn off and on the Cintiq to make it work again.
Sorry for all the try this and try that. We need to lean what the right solutions are. 🙂 It’s all new to me. 🙂