[Plugin:WP e-Commerce] Products with Variations require tedious updates to price

I’m currently working on wigs store. For each wig I have different sets of variations, for ex: Length, Density, Hair Type, etc… Each variation has its own price. Customers will be able to customize each wig.

The problem I’m currently having, is that when I add a product I have to add each variation and edit them individually. I thought the prices would automatically add up but not in this case.

Am I missing something?

Here is the example of working on:
http://mym2webdesign.com/addicted2hair/products-page/custom-lace-wigs/

Thank you in advance.