The reason some people can't close the options screen when they install BUG as a mod is because the Readme has a bug in it.
When installing as a mod, you must name the folder "BUG Mod" to match the INI file.
You can name it something else if you want, but you then must modify the "modName" variable in "Assets/Python/Contrib/ModName.py" to match. It's just easier to call the folder "BUG Mod", though.
I have updated and committed the readme.
@Cammagno - Can you please update the Italian version. I made a bunch of other changes to the readme (some formatting, some wording, some capitalization). It's hard to stop when I get started.
@LudwigII - Would you be so kind as to update the German translation please?
@Anyone who got bit by this - Sorry, and could one of you verify this works for you and post here? If it works. You'll need to move your "BUG Mod.ini" back into the "BUG Mod" folder as well. The game will look in your "My Games" folder first, so make sure it exists in only one place.
@Thornburgh - You provided the key piece of info here, so thanks!
Once you posted that a "BUG.ini" file got automagically created by Civ4, I knew that the mod folder must have the wrong name ("BUG" instead of "BUG Mod") because it will create the INI if it doesn't find a matching one.
Of course, had I actually *ever read* the readme, I would have found it sooner.
My bad. Did I mention that coders are allergic to documentation.