If the Linux version gives an error "no application installed for executable files" then right click on the BittyKnight file and select PROPERTIES > PERMISSIONS > EXECUTE > Allow executing... and it should wok
I used Raylib and Go to make the game, so everything is coded by hand. If you want to look at the code it is here https://github.com/unklnik/bitty_knight Not sure what you mean exactly, 'scene management' explain more and I will answer.