When opening a drawing, there are no lines only dimensions?
The main reason for this would be that the drawing may well have been created in a vertical version of AutoCAD (i.e. Architecture, MEP or Mechanical). You will need to install an object enabler. This can be sourced from the Autodesk support website or from your subscription site. If you have problems trying to find this then please do not hesitate to contact Cadline support.