There are several water sources. We use Deer Brook when we do the Range. We start light (0.5 liter each, and go quickly in the early AM chill over Rooster Comb and Hedgehog. Deer Brook crosses the trail right near the junction with the W. A. White trail (which comes from the Ausable Club). After this junction, you start going uphill immediately toward the Wolfjaws. Deer Brook will be on your right. It may look dried up, but after you go up the trail a couple hundred feet there are a couple little pools where I've always found water. YMMV.
Of course there are a few little brooks on the way up Rooster Comb that you can use, too.
Regarding the summits, it's not really possible to count them very well. On the direct route, you will no longer summit Rooster Comb, which now requires a short side trip. After you pass the Rooster Comb junction, you will continue up an down over a series of summits, all of which are Hedgehog. You know that Hedgehog is over when you get to the W. A. White trail junction, referenced above. Now you are actually climbing LWJ. There are a series of summits here also, including the Wolf's Chin, and I've seen people be confused. Here are the landmarks: After the Chin, there is a short steep, obvious downhill. (At the bottom of that downhill, you'll see the faint path from the Bennie's Brook slide coming in from the right, if you look for it.) You'll know you are climbing LWJ proper when you climb the very steep, wet, open V groove for about 30 feet all on rock (with extensively beat up woods to the right from folks avoiding the V groove). From there it's steadily, but less steeply up all the way to the summit of LWJ. The summit is obvious, with a trail sign, a decent sized pounded out area, and views of Marcy.
Hope that helps!