- fixed the name self-insert in save dialog file for GCode; added protection in case the save path is None

- fixed FlatCAM crash when trying to make drills GCode out of a file that have only slots.
- made the shell toggle shortcut key work when focused on Selected Tab; toggle units shortcut also
- changed the messages for Units COnversion

FlatCAMGUI.py

@@ -1508,6 +1508,12 @@ class FlatCAMGUI(QtWidgets.QMainWindow):
         if event.key() == QtCore.Qt.Key_3:
             self.app.on_select_tab('tool')
 
+        if event.key == QtCore.Qt.Key_Q:
+            self.app.on_toggle_units_click()
+
+        if event.key() == QtCore.Qt.Key_S:
+            self.app.on_toggle_shell()
+
         # Show shortcut list
         if event.key() == QtCore.Qt.Key_Ampersand:
             self.app.on_shortcut_list()