The issue for that system is moot now since my son needed the system and has taken it to his apartment elsewhere. I don't have access anymore.
I believe the one that bit me was the one you described as #3. I found a bugzilla item ultimately after reading the "how to" articles on opensuse.org where other people were having difficulties with dual boot. »bugzilla.novell.com/show_bug.cgi?id=781688
I tried a few legacy (non-UEFI) type installs, too, and it would consistently fail at first boot. I succeeded once in my several attempts (perhaps that was the time when I said "use grub not grub2" for the bootloader, but I can't recall for sure now. I did succeed in with a UEFI install with just opensuse 12.2 once, but was testing and that install got blown away with subsequent testing.
I also tried an install from the opensuse 12.2 KDE-live CDROM, too, with no better results.
I'll be ordering up components soon for a new build for myself. Not sure if I will go with the same motherboard I got for my son's build (Asus P8z77-V pro) as my requirements are different than his were. Linux will be a hard requirement for me, and if I can't make it work I'll be looking for help.
If I had had more time, I might have tried another Linux distribution, but I'm used to opensuse so was sticking with that for the recent build attempts.--
nohup rm -fr /&