How to add discounts in virtuemart 2.0 which are dependable on types of shoppers

Question

I am having frustrations with this new Virtuemart 2.0.

First of all:

I would like to define discounts. I can't find that option. How can I do this?

Second:

I would like to define three shopper groups and would like to define different discounts on product subcategory level per shopper group with the ability to have some subcategories invisible for selected groups. Is this possible, how can I do it? If is not possible, could someone give me any direction what to change in vm code to make this feature possible?