Help with lofting shape along curves

Hey all,

I know that this is so basic, but I can't remember how to do it. I need to loft a shape i made using curves along a number of other curves.

I can do it using polygon curves and the like, but can't manage to do it with the curve I created.

I haven't explained it all too well, but I have attached the files which will hopefully shed a little more light on what I want.

Thanks