Does the counting code go into the main loop just before the interrupts?
The "counting code" IS the interrupt(s).
Your main problem is to get the two halves of the code working I think.
When you have a working counter and a working display it will be easy to merge the two. But trying to get everything working at once just makes life harder.
So you say my interrupt code doesn't work, it wouldn't be the first time :), can you post what you are using?
Rob