Not sure that you can prepare for either the group ex or the 'card game'.
I would suggest that you 'actively' participate in the group ex without being dominant. If the group needs a little steer, say on the timing, then politely mention it. Treat everybody as a peer, don't be bossy. You won't necessarily end the exercise completely successfully but they do want to see how you interact with others - think CRM.
The card game was hard work. Lots to do in so little time. I did manage to get answers down for all of it but I don't know how much was actually correct. Some folk in my group didn't anywhere near finish but still made it through to the sim. Be warned, the examples they initially give you to practise are much easier than some of the sections you will encounter. Its all about deducing answers from information given. You don't have to assume - the facts are all there, if sometimes a little buried beneath other superfluous info.
Make sure your tech is up to scratch for the written test and the interview.
Best of luck. I quite enjoyed the day.