It's difficult to predict what may come up in the exam because they are supposedly written several months in advance.
General Studies is a weird exam in that you can't really revise for it in the traditional sense, the best thing to do is just keep up with the news and have a general understanding of what is going on in the world. That being said, I would be surprised if the EU question wasn't mentioned at all in the exam paper.
The best advice I could give is making sure that you read the question carefully. Of course the question in this paper are far more open ended than what you would find in a subject like History but that means that you have an opportunity to apply your own knowledge and understanding to a topic. For example in last years culture paper I applied what I knew about the Columbine shooting and the media's subsequent scapegoating of the videogame Doom in reference to a question about the extent to which parents should monitor their child's use of technology. That's a pretty morbid example but I think it shows how you can call upon nearly anything, so long as it is something that you feel is relevant and valid, to help write your response. The questions on the A2 paper seem to be more open-ended than the AS questions and I think it would be wise to give yourself some kind of focus so you don't get sidetracked or lose focus on what the question is asking you to debate. For example, when looking at a question from the 2014 paper, "Examine the preposition that the 21st century is the best time to be alive", try and narrow it down to a few ideas. One point I can think of off the top of my head would be the argument that we have more civil liberties than ever, but then I would try to balance that assertion by arguing something like "but not everyone is truly equal, differences in equality in parts of the world etc.", using any possible examples to support that argument, and then summarizing my point. After you've made the points you want to make, write a conclusion, even if its a short one. It just helps to round off the essay.
My general rule of thumb is try to make 3 points but if you struggle to do that, just write two: you're better off writing two well-developed points rather 3 mediocre ones. Oh, and chose the essay questions from the selection that you feel the most confident about.
And a final note: RTFQ - Read the ****ing question!! Make sure that the response you write is related to the question and if you use an example - like my Doom one - link it back to the question!
I hope that this is helpful, and feel free to ask questions if you like.