We might be talking about different things...
When we talk about 'mouse mode' in ArtRage, we mean selecting the option from the preferences menu, as per the attached image.
You should still be using pen mode with your tablet settings. The only change in ArtRage is that instead of using the hi-rez tablet coordinates, it uses the mouse location to report the stylus location. It still uses the correct pressure, tilt, and rotation settings from the tablet
AndyRage's mantra for graphics engine code:
"Sure - how hard can it be?"