Geometry tangent to point along lofted surface

Hi, this is my first post, and I'm fairly new to grasshopper, I started yeasterday, so I dont know if this is something very complex, or very simple, but what I'm trying to do is create a tube from lofted curves in grasshopper, the tube would then be able to change size at different points through the scaling of the curves, ultimately id like to get those all down to one slider, but for now im fine with 6, along the lofted surface i would like to have a geometry that would be used as a module.  Now, i know how to raplace the surface with my module through box morph and bounding box, but when the subsurfaces of the surface are then scaled, the module's geometry is scaled along with those.  I would like to know if anyone knows how to set it up so that when curves making up the lofted surface are not scaled the modules touch each other, but when the curves are scaled the modules expand and move away from each other and the growing surface underneath becomes visable.  I know this is a lot to ask for a first post, but tutorials havent been much help to me yet, and I've tried playing around with grasshopper and the move function to no real success. I thank you for any help you can offer, I'm placing an image of my current set up, though I doubt it will help much.