Good news about the lockups!
As far as orientation goes, the sizing of the main frame was inconsistent, for example, rotating an almost full screen window (not full-screen) from vertical to horizontal would often result in a very small window instead of one proportionally sized.
The most annoying thing was that the app content would often occupy a much smaller area than the window frame, and required a resize action (which is quite awkward in touch tablet mode, when you don't have a mouse or pen) before it would fill its frame. Occasionally, the app content would flicker repeatedly as it filled its frame, as if multiple sizing events were being handled.
As an ex Windows software developer myself, I've seen these sorts of problems before - Windows event handling can be tricky when trying to keep nested frame sizing synchronized.
