Basically you fight each boss, your times are recorded and then displayed back to you if you can complete all of them. The settings are pretty self-explanatory. I've only found one bug but it's pretty insignificant. If you hold down A when the main menu/game over/results screen should appear then it'll be skipped and send you to the Deku Tree boss room without resetting any data. If there is enough demand then I will fix it.