Cart66 and Acquisto WP theme resolution

I have created an online store with Wordpress, the Acquisto theme and Cart66 which are supposed to be made for each other. It's all set up with products and Paypal API but the payment system won't complete, hangs adding tax. Cart66 support told me: "The Aquisto theme has known javascript errors which are conflicting with Cart66 and other plugins. We have recently learned that the developers are not planning to update the theme to resolve these issues with Cart66. We would recommend 1) contacting the developers for a specific fix, or 2) switch to a different theme." Acquisto support told me: "As far as I know, there are no known issues with using Cart66 with the Acquisto theme. Either way, if you are having issues and need to move forward with something else, I completely understand. I would be happy to refund your entire payment at any time." I'm looking for someone to trouble shoot this final stage of the site as I like the theme and would like to keep it. Many thanks....Nick.