Great! I'll try those.
I'm also having trouble to get this microSD adapter to work, no matter what library I use.
According to the research I've done online it should work (I tried with an Arduino Mega 2560 and Arduino Pro mini ATmega328) and several different microSD cards, even an old 2gb card.
Does it require any special settings?
I'm trying the examples in the sd and sdfat libraries and can't get them to work with this adapter. They all work with no problem in a SD Shield (with SD to microSD adaptor)