Hi Michael,

Thank you for your response.
I replaced the qt lib to your updated version and it work!

Backspace key work as 'Delete' shortcut.
Enter and Tab are recognized as UI shortcut (I think this is correct behavior).
Other keys show same behavior but they aren't meant to used as a shortcut key as you said.

It seems that the updated version of qt lib solved this problem.

Thanks a lot!

nemuneko