The following code from src/plugins/contrib/NassiShneiderman/NassiView.cpp doesn't work on Mac (it works with wxGTK, but not with Carbon or Cocoa based wxWidgets - it fails both with wxWidgets 2.8 and 3.0):
#if defined(__WXMSW__)
wxCursor copycursor(dnd_copy_cur_xpm);
wxCursor movecursor(dnd_move_cur_xpm);
wxCursor nonecursor(dnd_none_cur_xpm);
#else
wxIcon copycursor(dnd_copy_cur_xpm);
wxIcon movecursor(dnd_move_cur_xpm);
wxIcon nonecursor(dnd_none_cur_xpm);
#endif
Using wxCursor instead of wxIcon worked, but I'm not sure if that's the proper solution.
See also detailed explanation on http://docs.wxwidgets.org/3.0.0/overview_bitmap.html
Fixed in trunk.
Thank you.