I don't know how to play cribbage, so I'll just give some general suggestions.
Give each card in the deck a unique number and put all the numbers into a list. You can use a different list to represent cards in your hand. When you draw a card, take a number out of the deck list and put it into your hand list.
I dont know how you are keeping track of your cards, but try something like:
If A+B=15 then X+2->X
You may have already tried that, but I think that might work.
The only problem with that is that then the program to count it would have to be pretty big because of all the combinations for five cards. Also doing the runs would be hard. There is a cribbage program for the 85 at ticalc, but I can't understand it too well. Maybe I should try a little harder, though it could just be something that is different on the 85.