Please, click on the red area of the grouped surfaces. Same behaviour on the polysurface but I could not apply the red material. The selection point will be off the projection.
import rhinoscriptsyntax as rs
# Select surface or polysurface:
obj_ref = rs.GetObject("Surface to move", rs.filter.surface, True, False, None, True)
if obj_ref.SelectionMethod() == Rhino.DocObjects.SelectionMethod.MousePick:
clickPoint = rs.AddPoint(obj_ref.SelectionPoint())
test.3dm (88.9 KB)