I just got screwed by Kraken.  I shorted bitcoin, then entered a BUY/Stop Loss and it hit but did not fill.  the stop loss was ignored.  they offered me some KFEE ($50) nonsense as an apology but this is bullshit.  How the hell can I trade if it doesn't work.

Can someone recommend a good trading platform that lets me short BTC and ETH, and maybe DASH? 

Thanks.