01.- Yes, you can use this NPC ID:31756. This NPC have been use for OB server, but if you edit the AI or copy part of it, you can make you own Classmater and add extra function. (I'm assuming you know how to work and code on NASC).
Or search in this forum, I saw a couple people shared some classmaster for C4 I believe, but its not too hard to add Kamael race on that code.
02.- No, but you can search here or on other forums that have people shared some NPC Buffer for C4., I don't know if it can work on GF AI, but you can test it and see what happen.
03.- No, you might research a lot here or on other forums to find some scripts shared. I haven't seen here anything like that here but I saw some of them long time ago on other forums, I doubt the links still activate but just google it a lot.
04.- Apparently it works keeping everything, as far I know:
this is from MyExt64.ini:
; Enables/disables .looton/.lootoff (autoloot)
Autoloot = true
But if you are looking more features for a PTS server, I recommend use AdvExt64 GF extender, they have done pretty much everything you need and that pack its ready to go "Plug and Play", or hire someone else to do all those requirement you need but I bet it wont be cheaper.