so i just got off the phone with Samsung support, and both the basic tech and the higher level escalation tech ended up giving me the "we're sorry but some third party devices aren't supported with the universal remote so we can't help you" line.
the remote works great to control the TV itself, and my cable box as well, and it also does at least a serviceable job of controlling the volume and on/off on my receiver, but i can't get it to work with either my PS3 or my AppleTV (3rd generation, circa 2012). i haven't been able to find a complete answer on whether either of these should work or not. both techs started trying to help me, because of course they knew that many people have been able to get this to work, but when they realized i wasn't missing something obvious, they immediately retreated to "not our responsibility"
thanks for your help.