5 And mortal miseries does make her play.
play > game, sport; play (i.e. side-to-side motion of the scales)
6 So long she travelled, till at length she came
So > Thus
7 To a hill's side, which did to her bewray
bewray > reveal
8 A little valley, subject to the same,
subject to > under
9 All covered with thick woods, that quite it overcame.
overcame > overran; dominated