I'm pretty sure Ghaz's directions are correct regarding most of your questions, but the last one I'm not so sure on.
If so can the IC use said transport as his personal vehicle, or just sit in the vehicle as sort of a bunker?
I can only assume you ask this because you still have a little bit of 4th edition dedicated transport rules mixed in with the new stuff, but a dedicated transport in 5th just means that only the squad it was bought for can start inside it, not another squad (unless it's an attached
IC obviously), so once you have started the game it is just a vehicle with a transport capacity and anyone can be transported in it.