eCart 5 and Data Assist

Ok so I have a website that I am converting into a dynamic site and I have purchased the Dynamic Suite. I'm a little lost on how I should setup data assist and eCart to reflect how I want my site to run. My site is a ecommerce clothing site so I need options for different sizes and weight to reflect the price for t-shirts. I would like to use pictured buttons for size options on the detail page instead of drop-down menus. I am using the MySQL database that webassist offered and I have already populated the options, optiongroups, and productoptions tables for sizes. I have attached screenshots of them, will they work and what do I need to add?

Data Assist:

I have already ran the data assist wizard for my admin pages, but I know that you can't use multiple tables for the wizard so how do I incorporate or setup data assist so I can upload my products with the correct size and weight options they need?

eCart:

How do I have the ecart calculate the right price based on productprice, productsize, and productweight?

How do I incorporate my size-button images? For instance, I click on the large size-button and click the add to cart button, it plugs in the large size and weight into the order details?

Any help is appreciated...thanks