it surprisingly isnt all that difficult to add ur own programs and such to the rom with a kitchen. raid has given us all the tools we need in the tools folder. u can take your own cabs turn them into oem's then into ext's
http://forum.ppcgeeks.com/showthread.php?t=47505 is a cool place to grab oems. then you can drop ur exts in the ext folder and subfolders. it will cook in the program u dropped in. i started with buildos and imo is a little bit easier to use. i believe juicys is based off of buildos. for buildos u dont need to convert to exts just place our oems in the oem folder. u might give that a try first to get a feel for it.