The file upload behavior will create a server file name variable that contains the name of the uploaded file.
in the add to cart button, select the column to save the file name, click the lightning bolt next to value, and expand the WA Uploaded Files (File Field Name) binding group and select the server file name binding.
The button to add the delivery charge you would probably add to the checkout page. that will post to the confirm page. on the confirm page, add a set session value behavior to save the selection in a session variable, then create a change in the eCart object that uses the session variable trigger to charge a flat rate of 90.
for the per item charges, there are a couple of different ways to go about this, probably the best way is tyo add a column to the cart for shippingCharge.
in the add to cart button behavior, set the shippingCharge column to the charge for that item.
on the calcualtions tab, add a new calculation set the name to totalShipping. and set the calculation to:
[shippingCharge] * [Quantity]
on the shipping tab, ,create a shipping rule using the trigger number of items in cart is grater than 0
for the calculation, use Subtotal for column shippingCharge.