Just a couple observations though.
1. You should have went with 3/4 inch plywood for the floor. I don't think you're gonna get much life out of that chipboard floor even if you do treat it.
2. I talk to RJ last night about the position of the runners. I'm just concerned about the stress on the over hanging floor. Weight from bodies, woodstove, wives
, may cause it to warp in the future.3. Those are big floor holes and combined with the high runners, you'll be looking at drafts. Maybe you could design 12 inch (or bigger) plastic pipes the seat into them and go right to the ice and fish straight down em.
4. Find a scap yard and attach some type of metal runner on the runners. It'll prevent them from getting chewed to hell and they will pop out easier when you want to move it.
There is a ton of room in that baby! I can't wait to see all the winter adventures that will be born in that thing!
But, you really need to remove those running boards and move them right to the edge of your hut. Trust me.... this is critical. Once you do that get yourself a couple more boards to put in between the runners front and back. Then you can shovel snow up against the boards on all four sides and she'll be toasty warm and will last for years to come.
Them holes are pretty tight to the walls and if for some reason you had to fire up a power auger to redo them well lets say my knuckles are already hurting . Been there and done that . 
