524118 WP-Ecommerce plugin: fix or show variation grid

Hello I have installed wordpress 3.2.x and plugin wp-ecommerce 3.8.6.1 The ecommerce show tshirts, habits, clothes, so it uses two variations: size and color of a product. The plugin, for each product, originally shows two drop-down menu: sizes and colors availables. When the user selects - for example - size M and color WHITE, it shows "product available" or not. The problem: sometimes this calculation not work. Seems the product available, the user add it to shopping cart, and here it says "not available", as really is. The problem is only for some combination of variation. Two possible solutions I'm looking for: a) fix that ajax calculator (it seems a bug of latest version of plugin) b) show all the variations of each product in a grid (or a list), with quantity, so the user could easily select the available variation. Like the list present in admin product page (see the attached) but more simply: only name of variation availables, quantities and form where add the quantity to add in shopping cart. I prefer b) solution, please bid only if expert with wordpress plugin and specify for which solution you are bidding for. Do not send standard email. Feel free to ask further details. I could provide an example link. Thank you in advance