Standard stroke direction doesn't really seem to favor lefties or righties - there are strokes that are drawn left-to-right but there are also several right-to-left strokes. The character ni3 'you' for example has three right-to-left strokes, two left-to-right and two vertical strokes (one of which ends in a right-to-left hook), and only favors righties in the sense that the left part of the character is drawn before the right. And actually for writing longer pieces of text Chinese is arguably better than English, since you can write vertically and right-to-left.
Anyway, we've (finally!) secured permission to include the handwriting recognizer in the demo version of PlecoDict, so if you can wait for the 1.0 release to be out (hopefully only another week or two) you can download it and see if it recognizes your handwriting well enough to be useful. Our software does indeed support Windows Mobile 5, I'm not sure whether or not HWPen does but if you wait for 1.0 you won't need to worry about HWPen.