Hi Gunter,
you are using the show points of the curves that's not correct.
You can add points manually from the draw curve menu.
Add points snapping to the curve ends and middle as required.
The projected curves are only for the construction of positioning your points on the surface.
Hope that's clear.
The addons menu is part of Max's UI but you can activate the ArrayGem script by typing it in.
The question about the base surface is not for me I think it's for BurrMan.
Cheers
Barry