2001 Chevy Venture Service Traction System Light and loss o

I have owned this van for about 1 month and have had problems with the brakes from the start. About two weeks ago the right rear wheel froze up, and would not move. Had to get it towed. They replaced the right rear cylinder and both back rotors, shoes, and pads on the front disk units. Yesterday my Service Traction System light comes on. At the same time my cruise control has gone out. If I shut down the van and restart sometimes I get the light, sometimes I don't, some times I have cruise but most of the time I don't. So far if the light does come on I loose the cruise control every time. Also I am getting lots of break dust on my front right wheel but not on the other wheels. I am going to take in to mechanic but would like opinion on what the problem(s) are with the van.

Thanks
nlinecomputers