For those of you who want to know, I did have official .gma and.unl files form the last purchased update. I used those files on 2 different units and it worked fine - I have tried several different maps from here and it updates no problem.

If nothing else works, I guess your best bet is to purchase one last update and save those files - look at it as an investment. One-time fee and you'll have lifetime updates (compliments of this site). Not the best solution, I know, but better than the alternative. Cheers!