Promotion: 120 lbs in cart of specific products = 10% discount

Does anyone know if I can do the following with the promotion option in CS Cart 2.0?

I want to offer a 10% discount to specific products (that’s working fine!) based on the following conditions:

  1. User membership = ABC (no problem with this condition)
  2. Total weight of specific products (not total products in cart) = XX lbs. (XX = whatever weight I choose) - this is the one that isn’t working for me because the only option I see for a condition is TOTAL WEIGHT OF PRODUCTS which is taking ALL products in the cart and I only want to apply the condition to the total weight of specific products.
  3. Categories = categories (no problem with this condition although I would think this could drive #2?)

    I hope this makes sense. Can I add a new condition rule of “total weight of specific products” if needed? I am not at all familiar with Smarty templates but could learn.

    Thank you!!