I had upgraded my NDSi to the 1.4 version. At this stage I have been unable to get my R4i Gold card to work, even with the latest downloads.
SOLUTION: I purchased a EZ Flash Vi card, downloaded the V12 firware upgrade, ran this on another NDSi console and it upgraded the card. When I put the card back in my NDSi console it worked just fine. FANTASTIC - very happy girl!!!