Graphics is Graphics, doesn't run when the real machine is running.
Aliasing M codes. Do you have the manual, I seem to recall reading somewhere that you can alias both G and M codes. But I don't know how to do it.
Home position at center of X axis. Haas does (or did) have a Second Home option which has its own button on the console. You can program any position you want as the second home and it goes there when the button is pressed. I have no idea if it can be retrofitted.