MATVT v1.01
Thanks to @sweenwolf
It now supports more TV boxes (most Android TV boxes should work, please leave an issue in case it doesn't work on your box along with information on what can be done to help it if possible).
Also has a GUI configuration page, and mouse style / size along with Boss Key mechanism can be configured
There's a demo video by TechDoctorUK showing how to use the app at: https://youtu.be/UC7bPw2tG4c