I am trying to conduct a cultural heritage project which requires importing 2d shape file polygons/polylines which represent decay mapping of facades of a building, onto a 3d model in city engine. however, i am having trouble reading the shape files. they are either extruded in 3d space, separated by layer or completely mixed up, not making any sense. i am new to city engine and have to learn it in a small period of time. any feedback would be much appreciated.