Virtuemart child variants gone after overwrite plugin values of the parent

[Actlas]

I create a product with 2 child variants. Then I use a Generic child variant custom field to let the customer select which variant he wants to buy.
This way after selecting a variant the customer can still switch to the other versions on the product details page unless ... I "Overwrite plugin values of the parent" on these child products.

If I do that after selecting a child variant in the dropdown nothing appears next to the custom field title anymore (Version: .... empty).

Is this a bug? How can I solve this problem?

[Actlas]

To make things clear I added some screenshots. First the parent product with its child variants, Then the selected child variant. As you can see after selecting the child variant nothing appear anymore next to "Versie". Ik would still like to be able to switch to the other variants here. This works as long as I don't override the custom fields on the child products.

http://i.imgur.com/azJVbR2.png
http://i.imgur.com/r9AwA1d.png

Does anybody know how to deal with this problem?