Hi,
No you don't need to do anything about the registering.
There has not been any issues reported on the Profile command. Could you try with a previous surface or draw a couple of 3Dpolylines, edit elevation of some of them and triangulate them in CadTools, draw a 3Dpolyline (Alignment) ant test to create a surface profile.
I think there might be som problems with converting of the surface. If you are importing a surface from other software it should contain triangles of 3DPolylines or 3dFaces. After import you can plot the surface perimeter using "Edit/View" Surface.
To create a surface from other types of lines you can triangulate all triangle edged as separate surveyed lines (breaklines) by doing as follow.
Explode the surface multiple time until you get separate lines.
Triangulate all lines with the checkbox "Use lines as breaklines" checked and "on Layer" : Here you select same layer as your exploded breaklines are placed on.
After triangulation, plot the triangles and perimeter, snap a 3DPolyline between a couple of triangles and try to plot a surface profile.
/Lars