Posting from Reddit:
"
Well, first of all to get a RU-CBT access you will have to follow some simple steps, its not that hard with Google Chrome so you can translate everything.
You have to go to their website -> Black Desert ? ??????????? ???? ????? ?????????? ???? or use this link and jump to point 4.
Translate the website using Google Chrome
Click on the gray button "COMPLETE THE QUEST" then you will be switched to another page
Click on "GET ACCESS TO THE PTA", it will be a red/orange button, and don't forget to keep translating every page
Fill your email and password that you would like to use them to register
Now it will ask you to pick a nickname then click "Save and Continue" button
Fill your first name, surname etc and click "Save and continue" button
Now you will be switched back to the main website, click "GET FREE" button
You will have to create an account on vk.com so just click on "VKontakte" Button
After creating an account on VK, just press the "VKontakte" button again and allow access to your VK account
You will be switched back to the main website, just click "GET FREE" button again
Fill the email that you picked before, then click on "SEND LETTER" button
Go to your email "yahoo, gmail or whatever" and activate the account
Click on "Already confirmed"
In this step it asks you to activate your account by a Referral-Key which i will post it below, then you will have to press "ACTIVATE"
Okay i have to explain the final step.. to be clear when you activate your account, you will get another key and this key is like a referral system, you will have to ask 3 players to activate it then you'll gain the access to the incomming CBT, so you need to find a key to activate your account then start asking others to activate their accounts by your key, well its kinda complicated to explain but im sure you got it all.
Here's my Referral-Key : 121CBB05-073D-48FF-B3E9-456C46B1FDAE
Hope everyone has a chance now .^
"
For an english patch follow these instructions:
BDO Tome - English Patch
Obviously I changed his Referral-Key with mine.
It all worked without any problems for me.