I had the exact same issue... For three days I struggled... Then I decided to start a new. I deleted all security modlues from the AHP. I unplugged and removed the battery from the the Security console, and removes all batteries from the window/door sensors. Removed the cm15a from the wall and computer, and removed the batteries. Restarted the computer. I waited 10 mins. I reinstalled the AHP batteries, and re-hooked it back to the wall and computer. reinstalled the sensor batteries, then held down each sensor test button for 5 sec. then released. This set a new security code for each sensor. Reinstalled the battery in security console, and pluged it into the wall. Set it's switch to install. Went into AHP and added each new door/window sensor one at a time. and hit the test button registering it with the AHP and security console at the same time. Once all door/window sensors were registered with the AHP software, and the security console I proceeded to add the key fobs and security remote to both the console and the AHP software.
Low and behold it finally worked!! I have been struggling with one sensor that would not register for days. I had tried everyhting adding additional RF repeaters everything... After reading the instructions again for the 10th time. I noticed that it mentioned that after installing the batteries to hold down the test button for a few seconds to set a new security code. I do believe that I had one sensor that was just conflicting with some other unit. Following the instructions above although a complete re-install was very sucessful and I have not experienced any additional problems with the registration of any additional sensors.
I hope that this helps.
Kirk