The URC-9960 doesn't have a SLEEP button and it definitely doesn't have the SLEEP TIMER function built in, so your best bet is to use the TV's own SLEEP timer function. The only remotes that I know of that have sleep timers built in are the old OFA "Producer 8" series.

As for the Zenith, your best bet is to find a forum that specializes in hacking the service menus on TVs (and they do exist) then see if someone there knows what you need to do to fix your TV.

Back to the URC-9960, if you really want to get the most out of this remote, I'd strongly recommend that you check out