Charlie Cat Toilet Training Surprise Day 16 - Not much progress

Charlie using the shallow toilet platter - Aug 18/11. Have since switched to a smaller hole in the platter with flushable litter. Cats hate it. Especially Charlie. Day 16 of cat toilet training...several mistakes due to changes/stand off's with cats. Not sure which direction to go with this toilet training. Sometimes they get it and other times they don't.