Untested GTK3 change to use the new gtk_grid_remove_*() which were introduced in version 3.10. I don't have 3.10 installed yet, but will test this code soon. These allow me to remove a crude work-around in earlier versions that skipped over empty grid spaces. In 3.10 and later the grid should contract and remove the unused rows/columns. Might need a similar change in dw_box_unpack().

#include "winuser.h"
#ifdef DW64
2 RT_MANIFEST dw.dll.x64.manifest
#else
2 RT_MANIFEST dw.dll.x86.manifest
#endif