Add Plates in Maxsurf Structure

Hello,

I have created a model in Rhino by using LOFT command. Then I used SPLIT command to divide that surface. I divide that surface for Side Shell, Sheer Strake, Bottom Plate. Keel plate, Bilge... 

Then I saved the model in igs format and import in Maxsurf Modeler. But I have not find my divided surface. How can I do it?