See how the buttons' bitmap is a problem on the Mac build? We'll be hitting things like this. Here, it was just a bit of a change to what was called (SetBitmap vs. SetBitmapLabel) but we've got to start finding and cleaning these. On this shot, actually, the Status Bar shows that "No cal" is cut off there too.
In looking at the code, good use is being made of sizers and that's a huge help. In v1, for example, I also made use of simply changing the fontsize on one platform or the other to get things a bit closer.
There are others though that aren't so easy. Have a look here:
See how the Notebook tabs don't have the arrows on the Mac build? At least as of wxWidgets 2.9.3 that I have going here, that's the behavior in the "widgets" uber-sample as well. "Listbook" and "Choicebook" seem to give reasonable behavior for things getting larger than one can display, but "notebook" doesn't. So, at times we'll need to either bail on a good idea or hack around the issue (e.g., use a wxListbook on Macs and use a wxNotebook on Windows).
Those of us with both platforms at our disposal should be on the lookout for these kinds of things...
Craig