Geopak - Adding Vertices to an element in site modeller

Hi,

This might be a stupid question.

I have a element (curve) with known elevations at each end.  I want to create a point at the midpoint of the curve which i know the elevation of.  How do i do this without having to create a design profile?  Is there a way?  Am i missing something?  I could add a point but then this isnt associated with the line.

Cheers,

Frosty