For now are confirmed Fastidios and 8*6 crew. More are to be announced in future, till Mai, June.
You can expect a few local/balkan bands and 2-3 international names more. For now, we do not know even approximately who might that be.
There is a bus line from Zadar to Rijeka, of course. But, do not know how much does it cost or else. You should wait till the season starts... than should be more available lines announced and even, maybe, a katamaran, a quick boat or something.