To further assist in getting the curves of the HyperNURB mesh as close as possible (before making it editable) I've cut some dummy sensor dishes into it. The 'window' area protruding through the main command mudule mesh is about 0.5mm at it widest point. That could be fixed by adding a loop knife cut around my low poly control mesh but doing so would add many more polygons. So, Ive decided to get the HyperNurbs mesh as close as possible, make it editable and refine 'by hand'.