I'm updating a system that started out as a Windows Vista system.
When the automatic updating built into the Windows 7 Upgrade DVD did not work, I turned to WSUSOFFLINE as an alternative.
I got stuck at another juncture once and got unstuck by selecting Never Check for Updates.
However, I became stuck again at Listing Update IDs
I've worked around this by applying Microsoft's Standalone cumulative update for Windows 7 SP1
KB3125574-v4-x64
I'm now running updateinstaller again to see if it's unstuck.
Dave Russell