What tech does the AI not use and why?

[Urendi Maleldil]

I've seen the default AI use stellar manipulation as well as unique facilities. They can be modded to use pretty much everything else except:

Master Computers (properly)

Remote resource extractors (they can put them on ships, but they just won't use them)

Build ringworld & sphereworld components (not that the AI ever reaches the point at which it's reasonable anyway)