If you are able to write the user without problem and during password typing only the enter works, this sounds like a default feature of the VMs.
You can write the password and the system is storing the password, but the screen doesn't change. You're used to seeing a movement on the screen, like filling the characters with *, this behavior doesn't appear on VMs.
You can write the password even if you do not see activity on the screen and then press enter.
Please let us know if this solves the issue.
Carlos R. Hernández