Regarding crashes - this is due to a dynamic core, I think I've managed to reproduce the crash and would try to fix it this weekend.
Remember that this is only an alpha version, and the published build is only a first WinRT implementation of a DosBox dynamic core - so expect crashes and incompatibilities. They would be fixed later. Also this weekend I'm planning to add THUMB2 instructions to the dynamic core, this should noticeably increase performance.
Regarding touch screen. It is in plans, but in rather late plans - first I need to implement as much as possible of a standard WinAPI functions without adding extra layers of emulation code. And lots of programs would work as is - as the touch screen returns the regular mouse events to programs, and if the program don't process relative mouse movements, but use absolute mouse coords returned from OS - it would work just fine.