Modding help for my AAR

For my Baktrian AAR I'd like to do some moddings:

1) I'd like to change the standard bodyguards to the Baktrioi Hippotoxotai.
I already know how to change the starting bodyguards, but I'd like to change the default ones.

How do I do this?
Is this save-game compatible?

2) I'd like to change the recruitment possibilities voor the Haomavarga province into:

MIC 11:
Level 1: Thureophoroi
Level 2: Baktrioi Hippeis, Baktrioi Hippotoxotai, Hellenic Cataphracts
Level 3: Thorakitai, Promodoi

MIC 24:
Level 1: Saka Foot Archers, Saka Horse Archers
Level 2: Saka Riders
Level 3: Saka Heavy Cavalry
Level 4: Nomadic Noble Mercenary

For people who are curious what I'm going to do; this represents how I am going to roleplay integration of the region in my Baktria campaign. If you've looked well, you'll see it's made for a TypeIII-government. For more details you'll have to wait the development of my AAR.

3) I'd like to make some nomadic ethnicities available for marriage.

4) I'd like to change some city (and possibly province) names during the campaign. How do I do this?

1) I've answered this question in another topic, so I'll simply copy and paste the answer here. To change the default bodyguard unit, you need to edit the file "export_descr_unit.txt" (EDU), which can be found in "[RTW folder]\EB\data\sp edu back up". (If you are not using the trivial script, you should edit the EDU file in EB\data. The files are identical, but the trivial script will replace the EDU in EB\data with the one from "sp edu back up" every time you start the game.)

Search the edu file for the entry of the Bactrian bodyguard unit. In the list of "attributes" there will be a tag "general_unit". Simply remove this tag and place it with the attributes of the Bactrian hippotoxotai. This does not affect starting bodyguards, but any general coming of age after changing the file will have the hippotoxotai as bodyguard.

A couple of things to keep in mind:
a) Naturally, make a back-up of your EDU before you start editing.
b) In EB all bodyguard units are free of upkeep, as you already pay 200 mnai per turn per character. Bactrian hippotoxotai do cost upkeep, however.
c) According to Aradan's complete EDU guide, the A.I. will not recruit units with the "general_unit" attribute.
d) I am pretty sure it is save-game compatible.

2 & 3) EB's recruitment and trait files are pretty complex. I cannot help you there.

4) It is possible to change city names in-game, but not recommended as the script users the external name of a city to detect it. If you change the name, the script will no longer affect those cities. If you still want to do it, do a forum search. I doubt it's possible to change province names.

Thanks for your help, Ludens.

For the reruitment modding, some forum searching has given me some knowledge on how it works. But to get it completely I need to know what in another topic was called "the logic of the n/y-values". If someone can explain this to me, I might be able to figure it out myself.