The new game button on the main menu does not work. I uninstalled and deleted the folders. I then installed to a new drive. How is it possible the game is broken and no one else is having this problem? Seeing is this is a clean install, I know of nothing else to do.
On top of this, my account/login appears to be missing from Larian forums. Is this level of error normal for Larian?!?
I try to register a new account, so I can report the bug, and the cappcha keeps returning an error. I have no way to report the bugs directly to them because of other bugs. !@#$%
I then try to log in from another computer. It appears I am logged in, yet when I go to the forums, it has me log in again, and then tells me I don't exist.
I tried the main website and was able to log in there, and then summited a bug report there.

did you replace the C drive? that has your profile with save game data and account settings i (C:\Users\%username%\AppData\Local\Larian Studios\Baldur's Gate 3)... if it wasn't the C drive then your account has just been unsynced

Accounts; there are 3 different one: Gog account (the most important because it records you payed for the game) the Larian account [synced or unsynced] and the Larian forum account... even if you used the same email and password for all they are still different

Larian forum accounts don't work because Larian server is so out of date and modern emails like Hotmail or Gmail will not allow them... you have to email them [thats Larian] and they will bypass their busted server to set you up with a log in that works on their forums

Larian game account [covers cross saves for multiplay] and this account is what the game tries to sync with the Larian launcher... when you first made the account Larian should ask you to sync it with Steam or Gog and if you said yes to that then you should use your Gog account

how to sign in now = open the Larian launcher and see the top right where it says "My Account", it drops down to [account] or [log out]. that [account] links you to the Larian support page which you have already spotted is worthless but if you scroll down on that support page it has two buttions to sign in using your Gog or Steam accounts

if you didn't sync Larian and Gog then your old account is harder to recover and you will have to wait for Larian support to translate your request