help building a ring

[rev.jc]

I am building a ring for us to use, and to host our event in dec. I currently am planning a 20 X 20 floor platform with ropes around the exterior and a wrestling mat for the surface, I have two problembs I am hoping some of you guys may have some ideas for,

#1 the tension and weight on the ropes puts incredible stress on the poles and pulls the ring inward, is there anyway to brace the poles from under the platform to hold the poles down?

#2 I find moving barefoot on a wrestling matt to be easier than on a canvas cover, any thoughts on this and please answer from all different arts prespective being that our Warrior challenge has bouts in 7 different Martial arts!