A while? Only a couple of days I thought Paul!

Mardibloke :
I too had a lot of troubles combining a 10 gig with a 48gig, and I finally gave in : I'm only using the 48gig now, because those two seemed like an impossible combination.
I will buy a second 48gig in due time, and see what that gives...

I too had the same error you had, but I encoutered it because I used the 'old' car2.builder.image, which wasn't suited for the Mk2a's, only mk2's. The new builder (update two weeks ago) should have solved all those problems.
As many problems as I already had with my Mk2a, I never had any problems installing a consumer or developer build though.