Osu multiaccount

I did almost all the tutorials, I changed the unique id of the hard disk change the mac and the HWID and also the uninstallid all created the new account but when I go to login it tells me an error has occurred with the server help !!

use a VPN with IP that were not banned

First thing that i recommend is create a new partition of 20GB at least, then install you OS on it, when you logged in install A VPN (I use SoftEther, it works perfecty for me) then create your account and download osu, and you will be ok

Do we have to use VPN every time we log in? or only for first login which is needed fro account registration completion?
If every time, how do we combat the fact that we're probably logging in with a different IP address each time?

First, you turn on the VPN (I use SoftEther VPN Relay Servers) and create an account, then download Osu-Relife, install this program, check that it is enabled. Now you run osu! and you have a window, then click on Random several times and click on Load / Save. You come up with the VPN with which you created the account, enter the data and Done! As for mail, you can create it yourself. There you will receive messages about the verification of your account.

Osu-Relife: https://www.mpgh.net/forum/showthread.php?t=1421992