Hi James456,

If you just want to do a mirror, you don't have to go to Surface Module.

You just have to create the eliptical profile, select or create the reference plane from wich you want to do the mirror and select the mirror tag.

If you want to extrude that profile you have to create a spine line in the direction you want it. Then select your profile and the guide line and that's it. You have created your surface or solid without exiting Part Design.

Hope this will help you