I can only recall being refused entry to a place of worship three times: the main mosque in Sarajevo, probably just because the guy on the door was in a bad mood; the Hagia Irini in Istanbul, by local authority folks in hi-vis jackets who were pretending to work on it; and Carlisle Cathedral, because you don't get more than a few steps inside without paying. I've never had a dress code problem.

I did once prepare for stricter codes when visiting Turkey by carrying a skullcap as local men do - never needed it.

Banning photography is a GREAT idea. You can always buy or download better pictures than anything you could do with your phone, and mobs of tourists taking pictures rather than simply looking are a bloody nuisance. They seem to have some sort of magical ideation that says there's something special about the picture because it was theirs. Which there will be if you're including your boyfriend with his arm round that statue of the BVM, but just go home and learn Photoshop, please.