This is the problem: Suddenly, you double click on desktop wacom tablet settings icon, and it wont show the dialog. It appears to be loaded as it's shown down in the windows taskbar. I suspect is caused by change of resolution or some setting, maybe suddenly it sets the origin of the panel dialog at some 3000 thosand pixels to the right or something. I have digged that wacom_tablet.dat file to see if I fix it changing some value there, but looks like a log, a history, more than a ini for settings... And anyway does not solve it.
My solution is having always a very complete settings file done and backed up to restore (with wacom utility for this, which in previous driver versions did not exist) when this happens, but is counter productive: You change the settings even per each project(and software) needs. I have seen it happenning with Cintiq 12", intuos4 A6, Graphires, Intuos 1.
Is just me, doing something weird every time? I doubt it, is normal use, I am amazed that seems no one else had this prob(or nobody asked), happens often with typical use. Maybe is because am setting a shortcut in the desktop? Weird as it works perfect till some random moment...
(Have digged Wacom's forums and FAQs, then here, but nothing related to it... Neither in "related questions".)
The thing happens in Win XP, 7, etc. Done so during years in my experience, and several times at work, which is worse.