Can't open file on SD

[StanMOI]

I put many different ROM file on my SD,
with some one I have this message: "Can't open file on SD"
Why ?
Long name file ?
Wonder Project J - Kikai no Shounen Pino (J) [T+Fre1.1_GenerationIX].smc
Or some Characters are not supported ?
like "]" "+" ???

[sanni]

File name length currently is max 32 chars and file name + folder path together max 64 chars. It's a limit set in place to reduce RAM usage on the Arduino Mega chip.