I have not done the process since 2017 and I already had the public version downloaded. At that point, they sent a zip file with a password and all that needed to be done was use the password to extract the zip and stick the contents in the DSDPlus folder. They have since done away with that method but they should email you files and directions.
Important... Copy your password to a safe location as if you lose it, you would need to email DSD team and wait for the response. Kinda sucks when there is an update and you don't have your password. Mine is safe in my saved email and also in 2 different cloud storage solutions.