You might find that people are better able to help you if you were to condense your separate posts into a grow log =) Then we could read the whole process and offer pointers instead of giving solutions based on a snapshot.

These look to be coming along pretty well. Wouldn't worry much about the leaf you snapped, would prune it off personally. Sort of tough to tell from the pictures, but are your leaves lightly turning yellow around the edges? (will refrain from further comment until you confirm whether I'm seeing something or imagining something lol)

Your growing medium looks awfully moist, probably could hold off on the misting right now. Overwatering plants is pretty common for first runs.

Do you know what the temperature in your box is? Now that you're in Veg state the plants will take all the light they can get, as long as they also do not get too hot.

How is the air circulation? (This is where the grow log would make it easier, I am not ashamed to say that I haven't read your earlier posts XD)