Ok first thing first.
Guys remember to do some research on real life
coasters before you start building the coaster.
I cannot stress this enough, check the reference.
http://www.coasterquest.com/coasterconstruction.htm
There are some really wild real word designs out there.
Ok ill go question by question:
The Parrot
The track can be any way you want, (wood or steel) as long as
it is gravity based, like all real life coasters.
panki2004
In order to keep things fair, I would prefer it if you did not use a rollercoaster generation software. Remember the key of the challenge is the simulation.
-R

I hope two linked mine cars qualify as a rollercoaster.