Need Help! BobCAD and 3D printing

I recently came across a need for building a 3D model and am planning to print a prototype. I'm a bit new to the 3D aspects of BobCAD but have been using it with my 4'x8' Camaster CNC machine for the last year (I post as richf over on the camheads forum). I'm comfortable with creating surfaces but am finding it an extra level of difficulty to have to enclose all of them and give them thickness. I can't simply create one surface and then scale a copy to make an inner surface. Bobcad scales in all 3 dimensions and would sure be useful if you could scale in one or two dimensions at a time. Primary, it would handy to scale in X,Y only so I could put a top and bottom on an object without Z levels being different.

Anyhow, didn't mean to necessarily turn this thread into a technique question but wanted to see if others have had success using BobCAD for creating STL files destined for a 3D printer. Seeing some 3D tutorials focused on output to a 3D printer would be great - I'd imagine this is a whole new market segment that Bobcad could take advantage of. I'd also be interested in any software that might automatically add walls/thickness to surface objects or would do cleanup prior to 3D printer output.

I have V25 Pro with 4th axis standard. I think the software is really great value and recent V25 upgrades have really enhanced the value (love deform and stretch functionality and the simulation upgrade).