Toy Hauler Ramp Door Caved In

I have a 2011 Kz Inferno with a Challenger ramp door. (94x97) that they said is supposed to hold 3000lbs. While loading my Spyder RT-S (weight: 998lbs)with me on it (232lbs ~ conservatively!) it caved in the middle straight up top to bottom! Then while trying to get my Spyder off the ramp as the "innards were all bowed out, the sides of the ramp door crease!

I called Challenger Door and they told me it was my problem! They would not stand by their product!!!!!

I bought this in a private transaction, so no dealer warranties etc.

So now I need to load my bike for a huge rally (the Lone Star Rally in Galveston - Nov 3-6, 2017)

I don't want to by another inferior door so I want to make one using the existing frame. Questions:

2x10's (9) seated in steel angle iron - vertical and welded together to make on big internal frame? (or only out the three 2x10's for my wheels in angle iron vertical and put all the other 2x10's in horizontal?)
or
Horizontal with no angle iron, but 8" wide x 1/8 steel plate on the vertical seated into the 2x10's?

There are 4 existing springs.

My frame is only 1 3/4 outside dim's and 1 5/8 inside dim's.

I still just can't believe that a $46,000 Toy Hauler has a ramp door that is worth $2.00!

Any constructive advise would be appreciated!

Peace!