here's some working Backblaze settings

[ggg7125]

I took a fresh unaltered copy of nodetube and gave it these settings and backblaze began working, fully tested. Files get uploaded to backblaze and served to clients from backblaze. I didn't change any other env settings but these.
(the keys here are FAKE but you'll be able to see they match the format of the ones you are looking for in your backblaze account)
(first i would like to say, Bucket ID, as shown on backblaze's site, is not used for anything in this process)

.env.private:

• UPLOAD_SERVER=https://f000.backblazeb2.com/file/yourBucketNameHere
  Not Bucket ID at the end of the url, but the actual name you gave the bucket. Backblaze gives you this url after you create a bucket, but it could give you f000, f0001, f0002 etc, so to see which you need to use, upload a file to your bucket, then click the file to see its details, and you'll see "Friendly Url" which shows you which one to use
• BACKBLAZE_HOST_URL=s3.us-west-000.backblaze.com
  You can see which url it gives you by clicking your bucket on their site.
• BACKBLAZE_ACCOUNT_ID=000da867f08s5d20000000001
  Go to Backblaze > App Keys > Add a New Application Key to get this. It'll be called keyID
• BACKBLAZE_APP_KEY=K0007xVcePfop07llYnF8PdVZQDvU8A
  This will only be shown to you once when you first add the new application key as above. It's called 'applicationKey'
• BACKBLAZE_BUCKET=yourBucketNameHere

.env.settings:

• NODE_ENV='production'
  I'm only showing this because i only tested it works as 'production', if it doesn't work for you in 'development' try 'production', all im saying is I didn't test this.
• SAVE_AND_SERVE_FILES='false'
  Oddly, even with this false its saving the files to the local ./uploads folder AND to backblaze, and i have no idea why but maybe thats intended for a reason idk. But its definitely serving files to the client from backblaze, you can tell by clicking the image on your website until you get the raw url to it, which is a backblaze url.
• ALLOW_COR=true
  Not sure if necessary, Didn't test with false.
• UPLOAD_TO_B2=true
• THUMBNAIL_SERVER=
  I just left it blank, which is the default.

[l1ghtsword]

Nice work, appreciate you documenting the effort!

[BassOfBass]

@ggg7125
Edited your post for better readability. If you are completely new to github and/or markdown, read the formatting docs. Don't need to be super fancy, just use code when referencing variables/filenames and when you list something, format it as a list.
SAVE_AND_SERVE_FILES working even with backblaze settings enabled is not intended, however only @mayeaux knows a fix for it (or at least I think he knows), so it might take a while to resolve.
I might try your instructions sometimes later, if only to fill out the wiki, since backblaze integration seems to be quite cryptic in the current state.

[mayeaux]

Nice work. Are you able to add this to the Wiki?