Yannis
that should be fine. But latest Splaaat post suggests a specific Sandisk card model that he confirms working perfectly. It should be a faster version than the one you mention. Speed is not really important, so don't invest in super fast cards that suit digital camera shooting large RAW files.
Yes you should DEFINITELY install the beta system on your unit or no big cards will ever work.
Actually you should have stated right at the beginning which system the unit runs on…THAT'S WHY your 2 GB card doesn't work….and we have repeated quite a few time the best fixes the 2GB problem.
Splaaat's card:
best
I