Hi, great work done on OneCommander! I like this file manager.
I am missing one feature though which I am used to from other similar software:
It would be great if you could assign one key (typically it is spacer) to mark/highlight file in folder instead of Ctrl+... or Shift+... For example you want to mark 2nd, 3rd and 5th file out of list of 10. You hit spacer on those files to mark them and then copy them to other pane (would be also nice to copy them with functional buttons like F5). This speeds up daily workflow a lot.
Anyway, you are doing a great job already. Keep it up! Big fan here.