You're welcome! The heating plates are great! I was thinking about ordering one for myself too, it might be easier to adjust as they grow.
I've tried the nipple waterers in the past, but they always dripped and leaked and left a wet area on the bedding, which i did not like. Chicks need their brooder dry dry dry. Though I did find a fantastic very absorbent bedding material... stall pellets. That's what my feed store uses in their chick bins too. My chicks have done fine with a regular plastic waterer that screws onto a jar, I put it on a brick to keep bedding from scattering into it.
I googled those... the coop is roughly 4'x4' so should be a decent size for 4 birds, and a lot nicer than most flat-pack prefabs. Good choice. The run however, seems to have quite a bit of space between each panel and in the fencing itself. I don't know what predators are in your area, but small ones like snakes or weasels could easily fit inside, and raccoons could still reach through and grab chickens that wander too close to the edge at dusk or very early morning hours. I'm not saying it won't work, just fyi.