Ques. Re: Factions and Cultures

i'm making a mod, and have run into to somewhat of a stumbling block concerning the various factions and their realted cultures

i know that the factions are hardcoded to specific culture types, my question is, what exactly does culture affect? i asked this elsewhere but the response was somewhat incomplete. my specific concerns are: does it affect unit types?
does it affect ancillaries?
does it affect allowable building types?
and if so can these things be bypassed, in other words can i make units and building types and ancillaries factions specific instead of culture specific?

one more question concerning Roman factions. I know that roman factions have to be either allied ( default ) or at war ( as edited in descr_strat.txt ) and can not be neutral. my question is if they are set at war will they remain at war for the entire game, can they make peace? If they are set to allies, will they reamin allied for the entire game, or will they eventually go to war?

thank you once again, and i want all of you to know that i love each and every one of you motherf***** ( thats a term of endearment where i'm from, or at least amongst my group of friends ) you have all been extremely helpful and i greatly appreciate it ~:grouphug: without all of you who have helped me in the past the mod that i'm working on now would not even be as far along as it is. so thank you. ~:cheers: and i'm keepin notes, you will all get a special thanks in the credits once its finished.

-5000