Sale, Gifts, Coupons Pack not working

I just purchased the Sale, Gifts, Coupons Pack from your website.

When I go into a product and use the product special prices feature, it never keeps my settings. I can go in and set a new price — which works — but the checkboxes for show old price and sale price don’t remain checked.

So all people can see is the new price — please help.

http://wordpress.org/extend/plugins/ready-ecommerce/