If it helps, some more details. When I start the game, Romania mod it seems is loading (the messages over the progress bar say something about loading Romania mod), and when the game loaded, and I'm in the main menu, there is a label in the top right of the screen : Romania.
I don't have the ModularLoading setting in Civilization4.ini, and I thought it's because i have Civ4 vanilla upgraded to 1.61.
I even tried to add this setting (ModularLoading) by hand in the ini file. Still no result.
When I say it's not working to choose Romania as playable faction means I choose Play Now from main menu, and then press ok, ok, ok until I get to choose a nation. In that screen Romania doesn't appear.