Sorry your thread got hijacked there, bud. As for your questions, I think just about everyone ties the end of the traveler to the end of the mainsheet if they have separate lines. The knot is usually tied at a point to allow almost maximum traveler play to keep the traveler car from exploding by impacting the stops on either side of the boat. I use a single line with a figure-eight tied at that point - there really isn't much difference.

I wonder, from your questions, if perhaps your mainsheet might be too short. With the main and traveler connected, you should be able to sit and trim from the front beam in light airs, to being fully trapped while up near the front beam in marginal conditions. There shouldn't be any tension from the retainer bungee in these positions - that is your maximum distance. Trapping out in the normal skipper position should leave you with some slack either on the tramp or in your lap.

In most conditions while close-hauled, you will have the traveler centered and play the mainsheet. If it is connected to the traveler or you have a single line for both, then it is easy to fish up the traveler to drop the car an inch (or more) if the wind really picks up.

For reaching in most conditions, you can ease the traveler a couple of inches (probably a little more since your Nacra has a boomless mainsail), trap out and continue to play the mainsail. A sharp crew can help out a lot by either having the traveler in hand when it's woolly, or help control pitch by playing the jib to keep max speed.

Down wind, your traveler position really depends on the type of boat and the conditions. Boats that have booms and spinnakers might ease the traveler significantly when rounding the windward mark, but often it is centered again shortly after the spinnaker is hoisted and trimmed. Boomless rigs like the Wave (if equipped with the optional traveler) certainly ease it to the fullest extent. There's a lot of variation in between. What are you sailing? Re-read the first paragraph on page 87 of Rick's book and keep in mind that it was written some time ago. I think the second sentence, "however, the best way..." is more important than the first sentence "...just inside the leeward hull" in most circumstances.

To trim the main down wind, I know guys who only hold the traveler. This is more of a gross adjustment, however. I have been seeing more and more skippers that never cleat the main down wind, and work it quite aggressively throughout the leg.

Hope that helps and that more folks weigh in to get you going as fast as you want to go.