Ah yeah we all get those, but you get a one time option to change it. If you did change it and it did not stick then I have no idea, strange. You can even set a name for offline profiles as well.
I dont remember there being an option to change it. There was a if you PAY us lots of money we will change it.
Offline profiles, so you have to have a separate profile if you want to play offline, use some magical hidden option if you dont want a auto generated username.
so what other pointless restrictions can we find with GFWL?
when you go back online it will sync the achvs as well eventually!

