It eventually worked, but it didn't work on the one the tech support guy used on his end. I started with one device, got that to work and added the rest. He used a program to control my computer (similar to Team Viewer) and he created a new account and that didn't work, either.

I was using a GoldX serial-USB adapter and it worked for other remotes, just not that one. I had to make some changes to this remote a few months ago (URC said they didn't see any problem with the remote, itself, when I was having problems with it) and I used a different computer that actually has a serial port- no problems at all.