D3/ no valid shares yet

Unless you are sitting on a bunch of D3s stay away from bitcoin as your payout. The default NO FEE payout threshold is up there pretty good and at the rate of pay per D3 miner it will take a couple months to get there. if you lower that threshold you may lose up to a 2 or 3 days pay just for transaction fees.
Yes any coin in the drop down on your settings page. Just be sure to add the correct coin wallet address. 1 address for everything will not work.