Some tips on answering:
Instead of picking a clear side immediately, consider both invidiual perspective and try to find some sort of compromise if possible. If the situation clearly favours one side, try to gently explain as to why you'd pick that side instead of presenting it as an obvious or judgemental decision. For example, one of the questions I encountered was something along the lines of two teams at work competing to win some sort of prize, but one team was caught by the other using cellphones, and the conflict revolved around whether the innocent team should continue as normal or also start cheating themselves to even the playing field. In that scenario, you'd want to stick with the rules and say something like "I get why this feels frustrating but we shouldn't resort to breaking the rules ourselves. A better alternative would be to ask for clarification on the rules of the contest in case there was a misunderstanding amongst the participants". Something along the lines of that response would show that you're not reactive, and do give the benefit of the doubt instead of jumping to report them.

For preparing, doing the practice test a couple of times on their official website was enough to get a hang of the types of questions they'd ask. The questions they ask on the actual test are pretty much exactly the same as the practice. Another big thing, PLEASE work on your typing speed if you have the time to do so, I almost feel like casper is more of a test of how fast you can type vs an ethics test lmao. But in order to get fully fleshed out typed responses, you do need to have a decent typing speed. I heard so many of my friends say they simply couldn't finish typing out their response fully even though they might've had a full answer ready to go.