I agree with fosley.

I love these types of puzzles, and so I understand the rules. However, the way you have them worded here kind of leaves room for "interpretation". Maybe something like:

For each puzzle, replace each letter with one of the numerals 0 through 9 so that the resulting mathematical operations stand true. There can be no leading zeroes in any part of an equation. Within a given puzzle, every instance of a given letter will represent the same numeral, and each numeral will be represented by at most one letter (not all numerals will appear in every puzzle).

It just makes the rules a little clearer for those that have never worked this type of puzzle before.

By the way, this puzzle in particular as a good one. The E was the most difficult part to solve.

Great work, and I look forward to working on more!

Mike.