@rec head
Did your serial number populate?
Mine just populated with the mac address. I was still able to follow the steps but I can't control my atv4k via my remote either. Works fine from the command testing section of the driver though.
My two tokens look similar but are definitely different.
If you can control from the myServer command builder (in the driver) then you have the handshake correct and the issue is not in the driver but in the UI / macros / setting the ATV1 as "active" something along those lines.
The error message advises that you did not have the authentication bits correct.
If that is still current, then please redo that from scratch.
That should clear the error. This isn't macro related. It's handshaking between myServer and the AppleTV box.