Importing multiple user groups for price_access

-- HikaShop version -- : latest
-- Joomla version -- : latest
-- PHP version -- : latest

Hi,
I'm making an import with a lot of articles (starting out small but it will be large once everything works)
Most of those articles have 2 prices and 2 quantities ... price 1-> qty 1, from Qty 2 -> price 2 ... the regular stuff ...
HOWEVER, I want price 2 to only be visible to 3 (or 4) user groups ...
There is no problem if I want it for 1 user group (I can import price_access as "all|21" where 21 is the id of the user group).
However, HOW can I import something like "all|21,13,8"? when I try this some strange things happen to my articles ... products appear in categories they don't belong and translations get all mixed-up ...

I tried "all|21|13|8", "all|,21,|,13,|,8,", "all|21,13,8", "all|,21,13,8," ... none of these seem to work ...
I usually use ";" as a separator for the fields and "|" as a separator inside the fields ... "," appears in some product names so might not be the best choice as a separator ...
I also have access levels defined (Joomla!) with the correct user groups in them ... but how can I select those for import ... it appears only user groups can be selected ...

It seems that one does work ... thanks ...