Before you get too enthusiastic about 'tilt' support with TabletPCs, be aware that ArtRage wouldn't use the tilt option even if it existed.
We've tried to put testing in for the availability of tilt support using the Microsoft TabletPC API, but have had difficulty making that test work reliably. So in the meantime it has been removed.
In other words, ArtRage only supports 'tilt' and 'orientation' when using the Wacom WinTab API (the way most graphics tablets do it) but not when using the TabletPC API.
That may change at a future date, but for the moment ArtRage 2.x doesn't support tilt on a TabletPC, even if it was available (although I can't think of any TabletPCs which support tilt at the moment anyway).
AndyRage's mantra for graphics engine code:
"Sure - how hard can it be?"