As far as stock AI is concerned...
Chinese Fighter is like NSDF Scout with cannons further apart
Chinese Light Tank = Soviet Light Tank
Chinese Tank = BDog Tank + A little extra ammo
Chinese Walker = Soviet Walker
BZ and RO have the same AI, RO is a nice solid addition to BZ. But in the secret RO level, something is different: The AI units all act as if they've been given a direct order to attack you. Let's say a Walker blows up your tank in that level. Now as a pilot in the air, the AI Walker will immediately start aiming for you, and you will most likely die, as if the Walker was given another direct order to attack. You are never safe in the secret level, the enemy ALWAYS knows where you are, and is ordered to shoot at you. This includes the snipers too. If you get blown up or eject in normal SP missions of either BZ or RO, the enemies will not try to kill you unless you hang around close to them for too long or shoot at them.
Yes, I posted the cheat for the level and how to make a shortcut to it in SP videos thread. I also added it to the level selection of BZ Config 9000 v2.4 in downloads section.
EDIT: You keep saying "Spork was so kind to share the secret". But my source is Google.

I don't remember what site I got it from, but I definitely did not discover it myself.