IB's paper trading contains something that attempts to simulate priority queue. If you join the BBO bid or ask, paper trading system keeps track of size "in front" of you and counts trades happening at your price until the queue in front is exhausted. It also treats BBO size decrease as a signal that someone cancelled and you moved up in line.
Eurex, and all other exchanges where IB customers trade, should now be available for paper trading. The paper trading account of each customer is given the same permissions as real account, ie in order to be able to paper-trade Eurex you need you real account to have trading permissions on Eurex.