Your in my area of expertise now and we build walls on slabs on an Island every day. I have done the same thing in my garage as you are doing. You dont need a curb. Here is what you do, Bottom plate is ACQ (You will need to use ACQ for anything that is below flood level). Then frame the wall with doug fir. Use termite sheild. On the Island here we use MR (Moisture resistent drywall) on anything that may get wet otherwise we use 5/8" Fire Code drywall. (if there is living space above garage you need two layers of fire code drywall). Did they put bolts in the floor before hand? If not, you also have to glue the wall down.
Insulate if you want, other than that your done, use a good anti-molding primer like Kilz. You can also use wood looking plastic base trim if your afraid of water damage.
We always install radiant floor heat in any garage slab we do and if you have ever experianced it you would want it. It can be a little pricey if your home isnt using a boiler but smaller garages can be run off a water heater type unit. Just make sure they size the piping right or it won't work right and take forever to circulate through. When done right you don't mind laying on the 80 degree cement
If you have a question just ask and I'll help you out.
Sam
PS Steve, we are seeing many problems with tyvek on Ocean or near water front homes where it was installed behind cedar siding as the homes are rotting due to being "too tight" We only use it behind vinyl now. We are also finding many homes completely rotted from ground to ceiling that used EIFS siding. The studs are actually disintegrated and only the paint and drywall are holding everything together. We just rebuilt a 5 million dollar ocean front house that was completely gone that was only 6 years old.