Are you saying you have carthaginian listed as a requisitie culture for a new building? I have never got that to work (though I've only tried in BI).

You need to add the _name tags at the top of the EB file in order to get the thread text in-game. It is the name of your new building complex plus that suffix.

faction_specific images require faction-specific buildings otherwise they will sort by culture I believe. This is because the game is hardcoded to use the image of that culture which bears the same code name as the building level.