Multiple groups or custom PHP upon purchase

-- HikaShop version -- : 2.6.0 business
-- Joomla version -- : 3.4.4
-- PHP version -- : 5.?
-- Browser(s) name and version -- : various

We've got products set-up to add a User group to the customer/user after purchase of a product. (Via Custom Fields, User Group after...)

We need to be able to assign multiple groups (i.e. multi-select)

OR

We need to run some PHP code.

Is it possible to assign multiple groups?
If not, what is the best way to run PHP code to assign groups to the user?
I'm guessing a custom plugin.
However if a custom plugin, which trigger should be use to add the groups to the user AFTER the purchase has been 'confirmed'? [We have a LOT of orders with payment by check that are manually 'confirmed' later. We have to add the groups AFTER the confirmation process.]

Hello,

1. You'll only be able to assign your costumers to only 1 group after they purchased your product

2. In your case the solution will be to use the "onAfterOrderConfirm(&$order,&$methods,$method_id)" trigger. Here is the developer documentation for more information : www.hikashop.com/support/documentation/6...#onAfterOrderConfirm

I'd love to make the suggestion that in the next versions you allow users to be assigned to more than one group after purchase. It would greatly aid what we do with Hikashop.