I am sorry it’s not working the way you are used to, but in this case it’s not really about “my conceptions” – it’s about standard, normal security practices. Do not share accounts, on Windows or anywhere else security matters. It’s just that simple! Has nothing to do with differences between version 1 and 2 really.
Anyway, return to version 1 is done by decrypting any files encrypted or re-encrypted by version 2, uninstalling version 1, installing version 1, and then encrypting the files again with version 1.
Not quite sure what “2 unique logins on V2.x” means in this context. Two separate Windows logons, definitely. Two different accounts with AxCrypt, yes – but it’s inconvenient because we don’t support switching between accounts so you’ll have to clear settings between different usages.