Why can't I extrude a Nurbs curve along a nurbs path What is the protocol for extruding objects along paths.
I cannot find any user-friendly assistance in the manual.
I am not used to the CAD geometry approach as I have more experience with the older Finite Element packages, where the geometry was constructed then meshed. Extrusion, mirroring etc were intuitive.

Also, I constructed a nurbs path in the shape of a wheel section, and constructed what I thought was going to be a separate nurbs circle, perpendicular to the plane of the wheel section, running through one end of the section path.
When I tried to perform the extrusion, using E, and transform rotate, there appeared to be no control over the transformation re axis.
When I selected the nurbs circle, I found that it had merged with the wheel section.
1) How do I separate them, and
2) Can I perform the extrusion using this method?

I am using v2.76  on a fairly quick XP SP3 32bit 3.3GHz Pentium 2 core and a GeForce 6200, with adequate ram and hdd.
By saying extrude along a path, are you referring to 'Skinning'? If so, they have to be separate objects, then you use one as a 'Bevel' object to skin(bevel) the path. If you could post a screen shot and clarify this, it would help.