I've no idea either. Sometimes they are so smack yourself in the face obvious when someone tells you, but you can spend all day racking your brains trying to work it out. It took me AGES to work out what BM (or B&M) store meant! I gave myself a back hander when I worked it out because it was something so simple!

Sometimes they mean nothing. Some buyers just seem to like putting a string of random letters for whatever the reason. Or just a dot. If I get one of them, I'll give them feedback with just a dot or a random string of letters.

I've never worked out how people get the pictures and symbols in feedback though.