Reviving a Water Softener, need some help.

When I bought my house it had a Rainsoft AMC 50 CT water softener. The system had no salt in it and we had some other plumbing issues so we bypassed it and eventually removed it. We removed the system because water in our area is acceptable and we were hoping that we might remove a plumbing restriction that was causing a drop in water pressure. Ultimately we found no restriction, the water pressure in our area just plain sucks.

In any case we were visited by a rainsoft salesman a few days ago who did all of his tests and such and tried his best to sell us a system. Now the system I have is only 6 years old and they are "designed to last a lifetime" so I see no reason at all to spend $5k on a new system. My wife, however, has very sensitive skin and we would like to try it out. As such I am interested in re-installing my system. We figure that worst case we'll be out a few bucks worth of plumbing parts and an hour of crawling around under the house. Gotta add the cost of the salt too, but we think it's worth it to try it out. If it doesn't do what it's supposed to, we'll get rid of it.

I have mocked the system up to a water hose and cleaned the brine tank thoroughly. From what I can tell the system is functioning properly, it is just in desperate need of a back flush and everything will be good.

When adding salt to the brine tank, do I need to add water as well? The manuals I have been able to find say that the only maintenance the system should need is to add salt, they make no mention of water. This leads me to believe that the system will attempt to maintain the water level, but what about initial setup?

I did not get the chance to call Rainsoft before they closed and I was hoping to hook the system back up this weekend. In the brine tank there is a float on the water pickup. I assume that the water level should have to be up to that level at least. How much salt do I add initially? The manuals are woefully hopeless on this. Also, how long should I allow the salt to dissolve into the water before I do a manual regeneration?

I have tried to e-mail rainsoft and was simply directed to call them, yet, as I mentioned, it's after hours.

Any information on this would be greatly appreciated!