Armored Eastern Generals

[SubRosa]

Savegames from 1.0 will not be compatible with 1.5. So you will need to start a new campaign. As far as unlocking the factions goes, it is simple.

Go to: RTW\World\Maps\Campaign\Imperial_Campaign\descr_strat.txt

Make a copy of it for a backup to be on the safe side. Then open it up. You will see the beginning looks like this:

;

Custom campaign script generated by Romans Campaign Map Editor

campaign imperial_campaign
playable
romans_julii
romans_brutii
romans_scipii
end
unlockable
egypt
seleucid
carthage
parthia
gauls
germans
britons
greek_cities
end
nonplayable
romans_senate
macedon
pontus
armenia
dacia
numidia
scythia
spain
thrace
slave
end

Change it to look like this:

; Custom campaign script generated by Romans Campaign Map Editor

campaign imperial_campaign
playable
romans_julii
romans_brutii
romans_scipii
egypt
seleucid
carthage
parthia
gauls
germans
britons
greek_cities
macedon
pontus
armenia
dacia
numidia
scythia
spain
thrace
slave
end
unlockable
end
nonplayable
romans_senate
end

Do not change the rest of the file. Just the beginning section I have shown here.

The interface in the campaign selection screen is only made to display 20 factions, so the rebel/slaves are not shown there even if you unlock them as above. If you want to play them you have to move one of the other factions to unlockable or nonplayable. I put the senate in nonplayable, but that is just a matter of personal preference. However, if you do choose to play as the Senate do not click on the Senate tab, otherwise your game will crash.

[Psauniaus spartio]

armoured eastern general.......the most powerful cavalry

[Techno Viking]

They don't upgrade automatically you need to retrain them in a city with a imperial palace (governors_palace and above for barbs) after marians reforms.
check export_descr_buildings:

Spoiler Alert, click show to read: 

governors_palace requires factions { barbarian, carthaginian, eastern, parthia, egyptian, greek, roman, }
{
capability
{
recruit "carthaginian peasant" 0 requires factions { spain, }
recruit "barb peasant briton" 0 requires factions { britons, }
recruit "barb peasant dacian" 0 requires factions { dacia, }
recruit "barb peasant gaul" 0 requires factions { gauls, }
recruit "barb peasant german" 0 requires factions { germans, }
recruit "barb peasant scythian" 0 requires factions { scythia, }
agent diplomat 0 requires factions { barbarian, }
recruit "carthaginian peasant" 0 requires factions { carthaginian, }
agent diplomat 0 requires factions { carthaginian, }
recruit "east peasant" 0 requires factions { eastern, }
agent diplomat 0 requires factions { eastern, }
recruit "egyptian peasant" 0 requires factions { egyptian, }
agent diplomat 0 requires factions { egyptian, }
recruit "greek peasant" 0 requires factions { greek, }
agent diplomat 0 requires factions { greek, }
recruit "roman peasant" 0 requires factions { roman, }
agent diplomat 0 requires factions { roman, }
upgrade_bodyguard 1 requires factions { barbarian, }
}
construction 3
cost 1600
settlement_min large_town
upgrades
{
proconsuls_palace
}
}
proconsuls_palace requires factions { carthaginian, eastern, parthia, egyptian, greek, roman, }
{
capability
{
recruit "carthaginian peasant" 0 requires factions { spain, }
recruit "barb peasant briton" 0 requires factions { britons, }
recruit "barb peasant dacian" 0 requires factions { dacia, }
recruit "barb peasant gaul" 0 requires factions { gauls, }
recruit "barb peasant german" 0 requires factions { germans, }
recruit "barb peasant scythian" 0 requires factions { scythia, }
agent diplomat 0 requires factions { barbarian, }
recruit "carthaginian peasant" 0 requires factions { carthaginian, }
agent diplomat 0 requires factions { carthaginian, }
recruit "east peasant" 0 requires factions { eastern, }
agent diplomat 0 requires factions { eastern, }
recruit "egyptian peasant" 0 requires factions { egyptian, }
agent diplomat 0 requires factions { egyptian, }
recruit "greek peasant" 0 requires factions { greek, }
agent diplomat 0 requires factions { greek, }
recruit "roman peasant" 0 requires factions { roman, }
agent diplomat 0 requires factions { roman, }
upgrade_bodyguard 1 requires factions { barbarian, }
}
construction 4
cost 3200
settlement_min city
upgrades
{
imperial_palace
}
}
imperial_palace requires factions { carthaginian, eastern, parthia, egyptian, greek, roman, }
{
capability
{
recruit "carthaginian peasant" 0 requires factions { spain, }
recruit "barb peasant briton" 0 requires factions { britons, }
recruit "barb peasant dacian" 0 requires factions { dacia, }
recruit "barb peasant gaul" 0 requires factions { gauls, }
recruit "barb peasant german" 0 requires factions { germans, }
recruit "barb peasant scythian" 0 requires factions { scythia, }
agent diplomat 0 requires factions { barbarian, }
recruit "carthaginian peasant" 0 requires factions { carthaginian, }
agent diplomat 0 requires factions { carthaginian, }
recruit "east peasant" 0 requires factions { eastern, }
agent diplomat 0 requires factions { eastern, }
recruit "egyptian peasant" 0 requires factions { egyptian, }
agent diplomat 0 requires factions { egyptian, }
recruit "greek peasant" 0 requires factions { greek, }
agent diplomat 0 requires factions { greek, }
recruit "roman peasant" 0 requires factions { roman, }
agent diplomat 0 requires factions { roman, }
recruit "roman praetorian cohort i" 0 requires factions { roman, } and marian_reforms
upgrade_bodyguard 1
}
construction 6
cost 6400
settlement_min large_city
upgrades
{