The Mazatrol protocol is not published anywhere, so far as I know. We wrote software to upload/download to Mazatrols also, and it was like pulling teeth trying to get any information. We had some help from a few friends who had done it before, and we also had to resort to "evesdropping" on the communications between a Mazatrol and a "Brand X" DNC system.
Be aware that not all model Mazatrols are the same. If your software works with an M1 or a T1, it may not work on an M2 or a T2 (or a T+ or a T32, etc.). Frankly, it's a can of worms.
Do you want to try our software ? A demo copy is free for 30 days, and we've already done the work. The time you save may be considerable.
visit www.sub-soft.com and download the PC-DNC Editor version 3.4 If you need help setting it up, can help you by email.