I recall the Solveains have been active there as well as Macedonia, haven't been personally but recall there being sa forum with a few English speakers on it, i'll dig though my internet history and see if I have a link.
Don't know about bouldering but I'm going in august and there's lots of lead and top rope you can do. Guided days out in omis are about 30 euro and there's and island just off split that has some great looking sport routes although I can remember the islands name
