Kraken has the worst trading platform and customer support I have ever seen.
When the market starts to move and be at its best, the orders you sent keep failing. Today, I tried to cover BTC short position, but my orders would not go through on Kraken's website.
So, I contacted support, but of course, their customer support won't be able to attend to my questions for days and even weeks. So, it was of no use.
In short, I'm suggesting that everyone should stay away from Kraken because even if you can trade well, you will still have to deal with their horrible technology and non-existent customer service. I'll be withdrawing my money, and Will never trade with the account.