Two things... I just found out about the shackle deal tonight. I have a large shackle on the anchor and it barely clears with a lot of wiggling. Chain size is fine, just need the right shackle, no biggy.
Hammer, in that pic you have the boat in way, way to deep. The stern has floated up, lowering the bow. When I launch I have the tires in about 6" of water, the let her (controlled) roll off, won't have any problems at all. That's where you ran into problems.