Version 5.0.0 released with removed InSim Relay API which has been discontinued, and a minor breaking change in the OutGauge / OutSim constructor options.
It means that the email address is already used by another user account. Are you sure you don't have another LFS account with your new email address already?
When someone else gets access to your account and keeps requesting new unlock codes, you will see the e-mails in your inbox that you didn't request, which means you should immediately change your web password so they get logged out automatically.
I'd say it's recommended now but you can still opt out. However, it's going to be released as an official patch soon for everyone anyway.
Is there an issue that you have with the patch?
You can still use 0.7F without this test patch but you won't get the support for the recent security update and other updates listed in the release notes in the first post.
I don't think it's necessary or sensible to show the confirmation "live" before unlocking - it does show "Your user name was not found" when you try to unlock with a non-existing user name.
On the auto updater screen, the country names for download locations are not translated, even though there are lines for them in the translation system. Would it be possible to have them translated?
Yes, the 1 week waiting time is there for a security reason. If someone else steals your login details and logs in, then you will be notified and will have 1 week to update your password before they manage to change the e-mail address and you lose access to your account.
Can you describe what exactly you did in more detail? What do you mean it auto logs you out from the game? Did you unlock successfully with the new unlock code and then it went back to the locked state?
Scawen tried to help you, doesn't that mean he takes it seriously? We're just trying to figure out what the issue is. You aren't the only one having troubles with the unlock code. Please be patient.