Q1: I had this same problem with my CTX-D2. Much More replaced the fans and no problem since. You could try oiling the bearings to quiet them down, but that is the only thing you could do without replaceing the fans I think.
Q2: Here are my charging profiles that I have been testing with. I don't know if they are right or wrong, but I haven't had a problem yet!
Remember to take into consideration that this is for 4 cell Oval batteries that only have to last 4 minutes, but go ridiculusly fast! lol I have used both profiles for regular charging and am just trying to learn what's best.
These are for Trinity IB4600's.
9990mA (all the way) 8.0A
delta peak 09
9990 mA Then I vary from 6-9 amps depending on class, track, and temp.
I like to have my cells about 120-130*f on my way to the line. I use the MM Cell Heatsink 2 for the first 10 - 20 minutes depending on weather and battery temp.
Q3 and Q4:
I'll admit I don't really know enough on this subject to give advice. I am currently using a MM 24amp ps to power 2 CTX Platinum Chargers, a CTX-D2, CTX-Batt Heatsink 2, and another cooling fan; without any problems.
Hopefully some of this may help you.