Brake problems

I am familiar with the brake system. I've replaced the rear shoes and brake cylinder along with the springs. I did all this about a year ago. I replace the pads every so many months (free replacement autozone!!). I have been having a problem for about 3 weeks now. The ABS light stays on. When I come to a stop I have to be really gentle on the brake pedal. I feel like when I come to a stop if I use too much brake the rear brakes lock up. I have to press the gas pedal for the to "pop" I feel a little shake of the truck. This is very noticable. This past weekend I pulled the drums and everything looked perfect (except there was a crack across each brake shoe. I also replaced the front brakes. There was a lot of debris (rust from the rotor) that looked like it was could have been a problem for the speed sensors. When I put the brakes back together the ABS was still on, but no problems with the brakes. However today (4 days later) they started grabbing (or locking down) when I come to a stop.

I can not figure it out.

Several things can cause what you are describing. The cracked shoes however, are due to overheating and should be replaced. I have seen several cases where low quality relined shoes are assembled incorrectly. The lining will overhang the shoe on the outboard edge and drag on the drum causing them to lock up. (requires a VERY close inspection of the shoes) If the parking brake is out of adjustment it also can cause locking. If an axle seal leaks fluid onto the shoes they will also lock up. A worn brake backing plate can also cause the brakes to lock up. Might even be air in the rear hydraulic system. Check these items and post your findings. Then we can deal with the ABS issue.