I just put my S500 into a workgroup named the same as my Domain. I then created a couple of local accounts with the same login and password as my existing users. I was able to get to all the data in the shares just fine. Better than nothing.
I know this post is older then dirt but am running into this issue as well after raising the functional level to 2008. If you are still out there were you successful with doing this as I tried and am still not able to access. Wondering if i'm missing something. Has anyone else heard of a way around this? Thanks!