Hello, thanks for your reply.
<user's home>/.nx/config/authorized.crt
seemed a Linux path; I had not seen the .nx directory in the user profile.
I create an authorized crt with the public key but…it doesn’t work yet.
If I set authentication by key, I have no connection. It asks for username and passphrase (and doesn’t work with both my password and the key passphrase); if I set connection with normal username and password it works, but I don’t want that.