I have some 1/8" holes that I can see through on my Clam Nanook. It's from where I threw my auger on it (without the protector) and it poked through. I plan to when I was moving quickly to setup elsewhere.
I plan to use the Iron-On material on the inside of of shanty. It's a heavy denim fabric, available from fabric store or likely Walmart, just not sure if the heat up adhesive will be strong enough. Will try. My season is over.