How to access sketch line data from IGS

Hi,
I got this conversor set up from IGS to OBJ. It works fine for the conversion, but I'm having trouble getting acces to a few sketch lines from the IGS.
I know that Faces are shapeType 4 as TopAbs_FACE but I dont know which one is for the sketch lines. Debugging I've seen its index 0 so I'm assuming its TopAbs_COMPOUND but I'm not really sure how to implement the access the starting and ending vertices of the line (or lines) within the sketch.