1. I see no problems with that. I've taken at night with no problems at all.
2. It would only only help in any type of cycle of test boosters. In our research and one study done on the ingredient showed it increased the absorption of creatine above without so it will make it work better.
3. Honestly probably not a problem but it's always good to take some time off of things. Saying that I feel comfortable recommending 6-8 weeks then a few weeks off.