I'm a little wary of splitting video with a y-adapter because I'm afraid you'll lose signal strength and get a diminished picture, but I haven't actually tried it so I'm not sure what it would do. Would it make any sense to feed the TV in the other room from the zone 2 output? That would give you independent source and volume control for that other room, if that is appealing.

OK, I just tried my one s-video source (an old Dreamcast). Fortunately, I have s-video and composite video monitor outputs hooked up just for the heck of it. When the TV is on video1 (the s-video monitor output), the video comes through along with the OSD (both setup menu and pop-up). When the TV is on video2 (the composite monitor output), I get the same - full OSD support. Keep in mind that this is with an s-video source. I don't have a composite source to test, and of course a component source will not step down to either s-video or composite video monitor outputs.