Hi Minizao and thnak you for your reply. In fact downgrading is not a "solution". We need to upgrade virtuemart for differents reasons and smartaddons should test their extensions to provide the best experience to their customers. I'm waiting for a solution since a few days, and the smartaddons's answer is: reinstall the extension correctly.
First of all, i bought the template to be able to use the quickstart package and free my time to put my boutique online as soon as possible. I opened aslo a ticket, and they told me once again to reinstall the extension. I thought i could get a good customer experience with Smartaddons by paying my template, but it seems that once we paid a template or extension, nobody cares about issues we could met...