Hi, I'm new to this R4/TTDS thing... My son got a "Z card" as a gift and within a week the microSD failed... Luckily, before it had failed.. I browsed the SD and saw ttmenu... So when it did fail I dropped blank 2GB card into the cart and downloaded a software package from www.ttdsi.net and the cart worked... the only problem is that Pokemon Black and White wont load. I get the error "errcode=-4 please reset system". The nds files do run using the desmume emulator, so it's not the files... i hope anyways. Anyone deal with "z card" before? Gonna try the RetroGameFan Update v6.73 and report back.