Just bought GF and I'm trying to create a form to set pricing based on quantity. Will post elsewhere making a feature request here, but for the moment it looks like an extensive work-around is required.
I can't seem to get merge fields to display correctly. I've set up a dropdown field with a list of quantities, enabled values and entered prices as values. I then set up a product field with calculated price using this formula:
{Quantity:9} * {Quantity:9:value}
What happens is that both merge fields return the value instead of the first returning the label and the second the value. So if the quantity is 100 and the value for 100 is 8, then I'm getting a price of $64 instead of $800.
As an added oddity, this continues to happen even when I disable values in the quantity dropdown.
(Just as an aside, I'm confused by your documentation for the merge fields, since at several points it refers to the "field name." I have been assuming that this is supposed to be the field label, since I can't find anything in the form builder called a field name.)