Light Reading: New 0.8 MIC system explanation

Hey, gang. first post, long time player. GREAT MOD.

Question, i've read over this whole MIC/reform thread and still have one question:

I'm playing as the Romans and just went through the Marian reforms. Prior, when i went through the Polybian reforms I was still able to use my older Camillian buildings to keep armies of older units stocked. Under the Marian reforms it seems all of my old buildings (camilian & polybian) are damaged and unusable (even if i repiar them, they just "re-break" next turn). My issue is now i can no longer make skirmisher, archer, but most importantly cavalry units. I've built the highest level barracks in Rome, but no cavalry or skirmisher/archer are available. My armies are going to suffer some serious set-backs if there are no cavalry available for me other than the Illyrian light cav i can make in Segesta. So, long question short:
1.) why am i having so much trouble building "alien" cavalry units, even though most of my MICs are of level III, even some of my level IV (in egypt) have trouble getting to a high enough level to build cavalry. Is there a time limit that a settlement must be within your civlization prior to being able to access certain units?
2.) when, under the marian reforms will i be able to build archers, skirmishers, cavalry in level I MICs?

Thanks again, great job!

There are only 9 buildings allowed per building tree. In the Camilian/Polybian MIC tree there is a level 1 barracks then 4 Camilian and 4 Polybian 2-4th level MICs. In order to have another era, another building tree is needed. Since you can't upgrade from one tree to a different tree, the script places Marian MICs and damages Polybian MICs. Just tear down all of your Polybian MICs.

Rome is a faction that used heavy infantry. They didn't use a whole lot of cavalry or archers. There is no 'Roman' cavalry or archers in the Marian era. There are a few auxilia cavalry units in Gaul, Iberia, Germania, and Thrace. For the most part the Romans had to use allied (regional) missile and cavalry units when they needed them.

Not all regions have cavalry. Egypt is one of these regions. Do not expect all kinds of units from everywhere. The EB system is based on what kinds of units that historically a faction used from an area, what they would have used, or what type of natives would be willing to work for a faction. This leaves some places will little to no units to recruit.

And welcome!