Two additional questions:

1) What is the best way to add new products? Is it OK to use "products_id" of 0 and assign a unique Model?

2) This probably has no overbearing on anything but what is the default scheme of the timestamp of the generated files? I know at a minimum it's : "YYYYMMDD-HHMMSS" but I can't figure out what the six digit number at the end of the filename when generated.