COLORS homebrew for R4sdhc r4rti

Hello.
I have a problem i'm not able to fix.I want to use the drawing homebrew COLORS! on my nintendo DS. I use a R4 sdhc , from R4rts.com.(http://www.r4rts.com/).
But it never works, it speaks about "FAT "; maybe i have to patch it but all my try failled.Can anybody help me? how can i get a workin colors! for my ds tank?Thank you by advance.tony