If your studio instructors are doing the checkout and you have lessons with one of the instructors, I'm assuming your instructor knows what was said in your last Checkout, yes? If there has been no attempt to correct the problem by your instructor, then you of course you should mention it. You are paying for the expertise, and you obviously want to improve so by all means make mention of it before it's too late to really work on it before your checkout.

For your shoe issue, you may be wearing shoes that have too high of a heel causing your foot to slide a bit. You might be able to "fix" this with some shoe pads that will help pad the balls of your feet and keep your foot from sliding. Proper fitting shoes is a must, but it can be hard to find. You may need to try a different brand or type of shoe to get the best and most comfortable fit.

Depending on the shoe, you can try "mole skin" or you can try bandage tape on your toes to help cut down the rubbing.