FSX AI Carrier Creation Questions "Hard Deck"

I'm building an AI carrier in FSDS and I seem to be running in to dead links when it comes to the hard deck creation or I find G-Max answers. I expect I will have a number of questions along the way but for now can someone point me to a fresh tutorial on creating Hard decks in FSDS 3.5.1?

Here is my receipe :
  1. In Part DateDefs.txt (FSDS folder) create a line like this :
    helizone <?xml version="1.0" encoding="ISO-8859-1" ?> <FSMakeMdlData version="9.0"> <Platform name="helizone" surfaceType="CONCRETE" > </Platform> </FSMakeMdlData>
    Note : between helizone and <?xml... : one space and one tab.
  2. Create the deck, name it "deck" and textured it.
  3. Copy and paste the deck. Name it "helizone" and make it children of the original deck (in part properties choose "deck" in Part Parent).
  4. I delete all the polygons of helizone object... but not the top one, obviously!
Notes. The names "deck" and "helizone" can be different but the way is there.
Yea! Nice simple and right to the point! Thank you! My current flight deck top surface has 20 polygons, if I want my AC to be able to travel over any area of the flight deck I will need to keep all of them won't I? I'm thinking that's what you meant in line 4, keep all top facing polygons!
If your deck is ONE part (regardless the number of polygons or if it is a part made with jointed parts) you just have to copy/paste once. The only reason I deleted unnecessary helizone polygones is to minimize the number of polygons. But for more or less 10 or 20 polygons, it can be omitted.

Look this image of my next scenery, a chooper flight test in Chittagong.

The floor where is the helicopter have a central hole so I need 4 flat cubes to make it. Once the cubes finished and ajusted, I jointed them and textured the result. I copy/paste the new created part and it gives the helizone, the hard surface. The floor underneath have only one part, it is the top polygon of the cube that form the first floors of the building.

Hope I am clear...