> I think yes you can. Click on the asset you want to apply discount. And then on the left side there is a field "Put on Sale". There you can choose how much discount and time range for the discount. Hope this helps.
it says i have to wait 7 days
Yes, you can't put an asset on sale in it's first week - pricing regulations in some countries do not allow you to put an item on sale if it's not been sold for a certain period of time at normal price.