Most of the questions you ask are covered in the main CTC Wings thread in this forum.
- Maths questions involve basic maths functions - you don't use a calculator and you get 15 minutes for 15 questions. Brush up on mental arithmetic etc. Currency conversions, percentages, squares / cubes etc.
- You can get sample testing software for the aptitude part...cockpitweb do some. Psychologists say that you're either predisposed to pass or you aren't and that practice will not increase your score...make of that what you will.
- Group work is two separate group exercises...not much point in giving you the exercise details, you don't need to plan for them, just enjoy and be proactive whilst doing them.
- Expect questions on the life / job of an airline pilot, issues surrounding commercial aviation, basic technical knowledge of aircraft, motivation, ambition, past experience, examples of the above, airline business and marketing - nothing that specific but make sure you're prepared. You may get asked some obscure questions. I found it was less about catching you out and more about giving an answer to a thought provoking question that you wouldn't have been able to prepare for.
- For the pre-prepared questions, be honest, take your time writing it and think about it - not much more to it than that
Good luck!