How can I implement walls for specific factions?!

[edyzmedieval]

Hello modderz and sorry if this has been asked before, because I am a rookie.

1st question

Since I've just started learning about RTW modding, and I was wondering how can I add the stone walls to Dacia. Historically, they had walls, but in RTW they don't have.

So, how can I do this?!
And what do I need?! I noticed Adherbal's Wall Editor. Is this all I need?!

EDIT: I know how to add, I just want to add the textures, when they appear in the Building Browser, and on the battlemap.

2nd question

How can I mod the marian reforms date so they can occur at 200 BC?!

3rd question

How can I modify the game, so the cheat add_money can be introduced more than 1 time?!

Thanks very much,
Eddy