Stronger Cover Pro Car Canopy Portable Garage! 

Good and simple reinforcement job. That will definitely beef stability up. If you don’t mind, I have 1 idea/suggestion: If you’re looking for a little added insurance of the wood not wearing through the tarp fabric over time, I’d put either glue-on or peel-and-stick foam sill gasket on the tarp side of the wood. (I think it’s usually pink and about 3 1/2 “ in width) It’s dirt cheap, comes in good sized rolls, it’s thin (3/16”) so no added bulk and easy to work with (cut to size, shape). It also has the bonus of being waterproof and can protect the wood from condensation where the wood contacts the tarp fabric. Just an idea.

"That ain't goin nowhere"

If you get winds like i do 50+ mph you will be surprised that they survive it.

I'm afraid your building method of raising the walls off the ground may not be the best idea. That looks like it is going to cause problems when you get high winds because when they can get underneath the walls that could cause a severe amount of lifting which could prove disastrous to your canopy. Sorry to say this but it just looks like a bad idea. You want to block out the wind especially under the walls.