Yeah, my problem in particular was your use of a number of unknown-to- me words combined with a lack of inline stack diagrams. Starting with, Leo Brodie doesn't cover ?do, just do.
Do you happen to know a suitable reference for looking up the meaning of such words?
Have a look at http://forth.sourceforge.net/standard/dpans/
Mind to explain your 0.r choice of name? What's the r for?
There is a standard word .r ( n len -- ) that prints a number in a field at least len chars long, or as much as needed. My 0.r does the same, but fills to the left with zeroes instead of spaces. The "r" stands for "right(-aligned)" I believe.
Segher