line-item

I try to setup a commerce site where the customer can order prints. The prints can have choices of papersize and paperquality. These are setup as attributes fields at a new product type called print.
Beside that the customer has to upload the picture he wants to get printed. Therefore I created a custom line-item with a file field to collect the file. Then, after creating the product display, the product shows up ok with the two selection fields and the file upload field.