As PP mentioned, there aren't direct buses from the waterparks to the themeparks. You have to transfer at a resort. For TL to AK, I'd catch a bus to AKL then catch a bus to AK. For TL to Epcot, take the bus to the BC and walk to the International Gateway entrance. For DHS, take the bus to BW and walk. For MK, take a bus to CR and walk.