Hi Maxi, apprently you are using very old version of Asymmetric Template. We have improved things a lot in the asymmetric Template since you purchased.
For example, if you visit our Live Demo with your phone;
demo.flexiblewebdesign.com/asymmetric/index.php?option=com_virtuemart&view=productdetails&virtuemart_product_id=20&virtuemart_category_id=1&lang=en
you will see the difference. Right now, while touching with 1-finger to thumbnail activates the LightBox popup, touching with 2 finger activates the zooming (just like how google-maps work on touch screen devices)
You can upgrade your template by getting the License Upgrade via:
www.flexiblewebdesign.com/license-upgrade
Regards.