[Plugin: WooCommerce Gravity forms] And dynamic field population

Hi

I have having some trouble to use FieldValue to dynamically populate a Product price Field in Gravity Form.
I am trying to create addons to products whose price are a multiple of the original product’s price. so i need to have a field that will display the original price so i can use it in the calculation.

Anybody has an idea?
i tried this but it didnt work:
http://stackoverflow.com/questions/16878127/gravity-forms-field-values-not-working

I am using Woocommerce, Gravity Forms, and woocommerce-gravityforms-product-addons.