I found in my dictionary that　ぬう shows the motion of sewing with needles ,so the needle of compass goes like that.

Lyrics is usually made up of figurative meaning, and I think this case too. Because this lyrics says that the compass of the figurative heart sews. And an act of sewing is often related to surgery or operation done at the end of them, isn't it? So I think ぬう in this lyrics should be 'healing','curing', or ' taking care of' etc. And I think that 躊躇いshould be figurative sickness or mental trouble and 心のコンパス should be like a figurative doctor for the person. But I want to see entire lyrics of this song. By the way I like this lyrics, 太陽が逃げ出すまで遊んでいたい The band replaced 沈む(set) with 逃げ出す(run away) in the lyrics of 'sun sets'

ぬって = Sew

Comment by Akatuy is correct. I took a huge misunderstand. Sorry !

The others misunderstand about ぬう。　This word doesn't have any relations to sewing. This ぬう means 'to bypass or to detour' on the context.