Beyond 2 instances you need virtualisation, if you don’t know how to handle it yourself, some software can do it for you, like ISBoxer. Those software usually allow some additional features, like mirroring keyboard and mouse to all instances, etc.

The notorious ones like ISBoxer, yeah they are safe and used by a big enough community.

For the catnip licence, I don’t know the solution, but I think I remember someone giving a workaround somewhere in the forum, I just don’t remember where ^^’

As for ISBoxer, maybe it comes from a setting mirroring input? I’m not using it myself, so I’m not going to be much of a help, but their community forum could troubleshoot this I believe.