Plugin will create light that will follow you and any other player on server even in vanilla minecraft! You can have your torch in right as well as in left hand or you can drop it on ground and it will emit light
The turn on and off functions only works for you!
Yes you can make dirt or any other block emit light when in your hand or when droped
To avoid any bugs I'l suggest to turn off plugin with command when using shaders or any other dynamic light mod