It’s a couple of days old, but I checked the R4DS site on the off-chance that there was an update and lo and behold, 1.18 was available.
Update R4 v1.18 kernel 2008-4-24
1） Solved 2203, 2219, 2240, 2250 problem
I’m guessing these are more savegame solutions for commercial games
Anyway, as usual, I’ve uploaded it to a nice fast host for you to download. Remember, just copy the files over to the root of the R4 (Micro SD card) and overwrite all, there are no themes in there, so those won’t be overwritten. If it doesn’t work, I really can’t help you as it’s simpler than Paris Hilton.