Hello
When I add a multi variant custom field to a product, create child products, and on the frontend pick the child product from the dropdown on product detail page, ajax spinner doesn't stop loading (and it also creates aditional product divs equal to the nuber of child products created). With ajax disabled everything works fine.
VM: 3.0.16
Joomla: 3.6.0
PHP: 7.0.9
Sounds like some JavaScript errors. Post the link of your site so that we check the exact error which is causing the problem.
I've set up a clean template package on dev host, and it doesn't work there either. The only difference is i used generic child variant instead of multi variant here
http://megadeal.kujex.com/all-deal/computer-laptop/desktop-pc/test-proizvod-detail
You can see when you choose an variant, the ajax wheel doesn't stop loadind, and a two aditional copies of the product are generated.
It looks like a problem of your Joomla! template. Switch to any other standard template like Protostar, Beez3 etc and check again.
Please test the most recent vm3.0.17.4 first http://dev.virtuemart.net/projects/virtuemart/files
and just in case, take a look on your template files and remove the override for your category view
Updated to 3.0.17.4 but it only broke some parts of the site, with the same thing happening while picking the child product from the drop down. I reverted VM to 3.0.14
In VM config no overrides have been set .
When I change the Category Template, Category Layout or Pruduct layout in VM config to beez3 fruit - it doesn't work.
When I change the default template to beez3 fruitshop everything works just fine. It is probably a template thing, but i cannot see any errors.