The PkgAds now support simulation mode. In simulation mode, you can do everything you can do in normal/live mode. The difference is that in simulation mode, everything is simulated (fake).
So if you create a shop, send an order to auction it will receive bids from fake ads in a simulated auction, you will also receive a request to insert an ad. Just like in live mode.
Advertisers in simulation mode receive 1000 euro on their balance to play around with. Create campaigns, ads, graphics and let them bid in auctions.
See and test how everything works, get to know the system, before entering live mode.