In Orient, with Scale=Yes, you are prompted for the type of scaling you want (1D or 3D). Would this be possible for Orient3Pt? I really need the third point to match to a normal direction from a mesh that I am working into. So for me, the scale 1D would then be working between the first two points that you pick (almost like not affecting height).
My workaround at the moment is using a Sweep2 with MaintainHeight=Yes and then extracting an isocurve, which gives me the scaling between two rails (the first two reference points I would pick lie on these rails).