Where you are using UPS Rate look up to get the shipping amount it will be very difficult to display the amount saved saved by the "free shipping", it will require a fair bit of hand coding to accomplish.
You would have to have 2 UPS Server behaviors. one to look up the shipping rate for the entire cart. The other to lookup the shipping rate to be discounted. eCart was not designed to have 2 shipping rate lookup behavior for the same shipping vendor, so we cannot support this.
As for you question about adding the column to the cart, since you are using a database, you also have to create a column in your products table. In the database yopu will asign the value 1 or 0 to each product.
In the add to cart button, you will bind the cart column to the column from the recordset.
