Trying to setup first product

EDIT I can see the image now but still can't figure the other stuff out :/

All of my products will be downloadable products and I managed to get the zip file uploaded and eveything but my preview image isn't showing up at all anywhere and there's an error message on the shopping cart that says

"Please update your order ...
Product Name: Fantasy Backgrounds I ... Quantity Units errors -
You ordered a total of: 1 Units: 0"

And there's also a place under the product name on the product page that says "Model:" do I have to have this there or can I remove it?

Thank you in advance.

"Please update your order ...
Product Name: Fantasy Backgrounds I ... Quantity Units errors -
You ordered a total of: 1 Units: 0"
In the product entry screen in the admin set these to the defaults

Product Qty Minimum:      1
Product Qty Maximum:      0
Product Qty Units:        1

And there's also a place under the product name on the product page that says "Model:" do I have to have this there or can I remove it?
Admin > catalog > Product Types > at the right select "edit layout > Show Model Number > set to "0"

Thank you kobra!