I have a handful of bugs that need to be tracked down and fixed.
1) When creating a "Special" in the back end:
When you enter the ending date for a special product the format needs to be dd/mm/yyyy and then it will change it to mm/dd/yyyy. This is a simple uniformity issue. I could fix it but I don't have time. Also if you edit a special, the dates are not read from the db, but are reset to Jan 1, 1970 or something...
2) There is a bug of some sort in the Tax reporting tool that keeps some data from deleted orders... probably a problem with improper order deletion in some other module.
3) Somewhere the order total is not being rounded before it is written to the database. This is not a real problem except that it gives a difference of a penny in some cases between actual billing and what is on the invoice.
*I have a code identical test server that you can work on, and mess with so that you don't have to worry about the production server.