Worked for me - I am now running 10.1/5.1 hybrid, baby!
If someone wants a copy of this disc, I'll be happy to make them for a small fee. Drop me a PM.
EDIT
It doesn't work . The system won't let you enter an address or select a POI. (It does let you select a pre-entered memory point, but that's it).
So.... One must decide, whether they want new maps but no Override ability, or really old maps. I think we'll go with new maps.