Tried both things. Imported from my old Marantz RC5200 via ProntoEdit, apparently without a glitch. When I try it on the A/C, only the Off works. The On button is inoperative. When I learn the IR signal through ProntoEdit, sometimes it will import apparently OK, and others it will hang for a while without success, but it will not turn the A/C on. If I try to learn directly from remote to remote, my TSU7500 will often freeze and I will need to remove the battery to "unfreeze" it.
Thanks for the help.