Here's my problem, like many others: i can't play some roms i have.
I'll give an example:
When I tried to run the game, Rockin' Pretty (US), it wouldn't load; i only got a black screen.
Then I googled a bit and found that it could be a problem with my card's firmware. So, I dled the latest firmware and xmenu (1.45 and xmenu 2.56). Tried the game again, didn't work.
I formatted the card, loaded 1.45 and xmenu 2.56 and i tried the game again to no avail (still the same black screen).
I, then, researched some more and read something about arm7 fix. I arm7 fixed Rockin' Pretty with the recommended donor rom Sim City DS (J). I ran the game, though I no longer see a black screen, I got this error message "The save data could not be accessed. Please turn the power off and reinsert the DS card."
I tried a few more times, again to no avail. A while later, I changed the save format (by pressing Select + left/right) to see if it works. I tired all of them (EEPROM 4Kbit, FLASH 2Mbit, etc etc), but none of them work; I still get the same error message I mentioned earlier.
Please help me, I'm out of ideas, lol.