Howdy, Todd!! You're doing great, and you've already received lots of good info!!
One thing that I'd add is that the best feed for them is called chick starter. I particularly like Agway feed, and that's what I use for all of my livestock, including the chickens, but just about every feed company makes chick starter. The stuff you have looks just a little course for them, it could cause problems in their gizzards.
The setup you have for the chicks is perfect. You can adjust the light for heat by their reactions. Panting is definitely too hot. Also if they're all staying aprt from each other, it usually means it's too hot. If they're all huddling together tightly, it means it's too cold. But I'm sure you already figured that out.
You're doing a GREAT job with these little guys!!! /forums/images/graemlins/grin.gif