Thank you so much for your extensive input guys.

Yes Frenchy i see now what you mean about sweeping it first then using the generated profiles to form the loft sections.

Thank you Michael for your explanations. I have to say the more i am testing moi the more i like it and it is on my list for purchasing in the near future.

I am having a little trouble creating some planar surfaces which are a bit twisted but im perhaps asking the impossible! Also, whilst your here, is it possible to multiply a spline between two rails like a 2 rail sweep - instead of just the one rail? Or some way of equally dividing up a surface creating edges that can then be used to sweep objects along? Maybe that's a version 2 tool as well!

Thanks again,
Rob