Problems with Fonthack

I tried to use the fonthack TIFF program on my fw2.8 PSP, and I ran into a bit of a problem. I followed everything it said in the README (Dump flash, modify, fix flash, put font on fontmod folder, etc.), and when I start up the PSP everything seems to be working fine for the first couple seconds. I see that the font has changed in the Time/Date thing, but then it goes to the blue "Setting information corrupted. Press O to repair and restore default settings" screen. How do I do the fonthack without it going to this screen?