Yeah nice of them to suggest the forum like that. If this were snow leopard (10.6) we might have a clue as there's a known (and fixable) font issue with snow leopard and lion machines and FileMaker.
You'll need to spell out some more info about your solution and run some tests we will suggest if you can:
1) Is this printing done by selecting print from the file menu or are you clicking a button or otherwise running a script to print?
2) Have you downloaded the latest version of printer drivers for the Mac?
3) Do you have access to another printer you can try to see if it works? (even if you borrow a friend's printer to do this, being able to print on a different printer may provide a useful clue.)
4) If you create a small simple test file in FileMaker and print stuff from it, do you see the same issue? (Maybe it's a problem with the specific file.)