Zubrag, great job, this script is great, and I really appreciate you keeping it stp (short and to the point), and
free.

Please feel free to let me know if my suggestion is impossible.
I want to add new fields, and have the administration page automatically calculate the differences between them. For example:
User enters 100 into field x, and 103 into field y, then the administration totals the difference by subtraction is 3 for that user. If it wouldn't be a hassle, I would love adding a new row that shows the total of all the users would come to.
Yours Sincerely,
Ivan