I'm steam user and installed EoR on my mods folder. And When I played it, I set my launch option as "--features.mod=mods/EoR"(Properties >Set Launch Option)
And I launched it. I started my play as Byzantine Empire. And I just fought two battles. After I won over the Slavs in first and built some of buildings in my provience and abandoned encircled and hopeless province by destructing the buildings and raising the very high tax, and Move my troops from there to another region. And I ended the turn, My small troops had defeated by Slavs and some of my regions had the order issues. I lowered the tax and ended the turn, And I get troubleshoot. And I removed my mods because I think it is unstable.

I hope your developers fix it.