Re: two parallel rods
Ever since I saw the initial design with two parallel rods I have been wondering if that isn't a high risk launch option. There are several factors that could result in those rods not staying parallel during the course of ascent.
The rods being mounted on different parts of the platform structure 'could' result in either a convergence or divergence of the rods due to thermal changes and loading stress in the platform structure as it ascends into the colder regions of our atmosphere. This would effectively 'clamp' the craft between the rails during launch and wreaking havoc on the whole platform when the engine is ignited.
My suggestion would be to use a single rod and 'hang' the craft upside down on that rod. There is no up or down in space so the launch orientation is irrelevant.
Would hate to see this fail because it got stuck on the launch rails.