Login To Your Kraken Account
Click on the Export link under the profile dropdown menu.
Select Trades from the type drop down, select your export date range, and finally click the Select All checkbox to generate your trade history file.
Kraken will give you a trades.zip file by default. Unzip that file so you have the .csv that is inside.
Navigate to the Kraken tab on CryptoTrader.Tax and drag the file .csv file you just unzipped into the blue box.