Hi,
Thanks for rising this issue. I don't know how we didn't notice this problem before. Basically it happens because the jQuery library not being loaded in the subpages in our DEMO page
(but in the modern joomla templates, all joomla templates loads the jQuery library already in every single pages, simply because of the drop down main menu, maybe this is why nobody has reported this problem before)
The solution is so easy to resolve though.
Basically this file should be opened:
templates/YOUR_TEMPLATE/html/com_virtuemart/assets/includes/flexibleMartGlobal.php
and this line
defined('_JEXEC') or die('Restricted access');
should be replaced with this:
defined('_JEXEC') or die('Restricted access');
vmJsApi::jQuery();
And the problem will be resolved.
Regards,
Support