Nice idea, but i think a really relaxing and peaceful game should not have that kind of music stop and backward movement... There's still some challenges and that's the wrong point. But 4/5 anyway :)
To get the wings : Stay a few moment on the "sacred dais" one the left of the 10th rune.
To switch the bridge on : first get the wings, then switch on the lever on the platform above the 5th rune. then you have the spire bridge unlocked. the rune bridge lever is on the spot unlocked with the spire bridge. for the last brigde, the lever is hidden in a cave not so far from the 9th rune. to get in, go on the bottom of the hill, and jump through the left wall, above a tree.
To get the mushroom : explore the caves and unlock all the bridges.
To kill all the darklings : good luck xD
To kill the boss : His pattern is :
up open, up closed, down open, down closed (open and closed refers to the mouth, of course). You have to activate the last rune to kill the boss. just watch out of him, he doesn't kill, but eat you fairyflies. just avoid his attacks and switch the rune on when you have 5 fairyflies.
Good luck ;)
 "Take a Walk"){kind=icon}
 "Super Awesome RPG Platformer Shooter"){kind=icon}
 "Best Friends Forever 3"){kind=icon}
 "The Enchanted Cave"){kind=icon}
 "William and Sly"){kind=icon}
 "Music Catch 2"){kind=icon}