Hi Anne,
A couple years ago we finished (new floor, as opposed to refinishing) the new Ambrosia Maple floors in our entire house with Waterlox, and I do have a few tips for you. The first of which is to give you the link to the most knowledgeable and helpful place you'll ever need regarding Waterlox:
www.paintsource.net I called them a number of times with questions came up and never hung up without 1) an answer, and 2) the reasoning behind it. I think it was Doug I talked to, but it has been well over a year ago.
Most importantly it is imperative you know that Waterlox is NOT a layer/coat-building finish like Urethanes or most other floor finishes.
Understanding that fact is absolutely essential in that floor preparation is everything. If you make sanding mistakes or ommissions they will not get filled-in by your finish. Waterlox is tung oil-based and is therefore a penetrating finish that actually helps preserve the floor (as I understand it). Knocking it down with light sanding between coats makes a big difference, almost as great a difference as vacuuming up the dust and further prepping it with a clean rag DAMP with mineral spirits. I learned the hard way that the floor refinishers around here don't like it because of the extra work involved. In fact, mine ended up walking away from it over halfway through, never to be seen or heard from again. I'm not saying all of them would respond the same, but the "tip" is not to pay upfront, holding as much back as you can until the job is finished.
The rest is common sense: allow ample time for each coat to dry thoroughly before prepping for the next coat, and give it as much air as you can - the odor/fumes are unbelievably strong!!! Finally, I would recommend at least 4 coats, with being the Sealer/Finish before going to a topcoat. That about covers it and the guys at PaintSource will prove themselves invaluable.
We also did our Maple countertop in Waterlox, finishing with the Satin topcoat - we did this ourselves - and now years later it is still drop-dead gorgeous!!! Best of luck to you...and don't forget to post pics!!
Also, if you find someone really good, please let me know; we've got ~2800 sq ft that needs refinishing some day soon.
Russ