pframe and closest points problem

hey guys, i'm having an issue with orientating a curve profile back on to a road i am making. the definition works pretty well to make a flat top road using a curve as its sweep path and a profile to sweep with. i'm stuck trying to get it to buldge out at certain nodes. i've created circles and used the size and centrepoints to have a relationship to scale and strength of scale (i'm not sure how well it works as i havent got the profiles in the right place to test it)

i did this using find closest points, but then i can't figure out how to re-orientate the original road profile onto just the results from the 'find CPs'... it's probably very simple but i've stayed up all night trying to figure it out and now my brain isnt working...

thanks in advance