Your 3.204 install is corrupted. You need to first back up any .ahx files you have created (any file that does not have a 2004 file date) to another hard drive or a flash disk, then uninstall it. After the uninstall, delete the Active Home Pro folder in C:/Program Files and the X10 folder in Program Files/Common Files.
Next, contact X10 to get the current version of AHP, 3.228. When you get it, do the following: 1. Unplug the CM15A and remove it's batteries and unplug the USB cable. 2. Replace the batteries, but don't plug it in to AC or the PC. 3. Install AHP 3.228. When the install is done, shut the PC down, then plug the CM15 into AC power and its USB cable to the PC, then reboot the PC. When it has booted, go into the Control Panel ,System and the Hardware settings, make sure the following key is present under USB Devices: X10 USB Active Home (APCI Compliant) - that's the CM15A.
Now open AHP, when it opens, go into Tools/Hardware Configuration and set your time zone and location and upload that the CM15A. Then open either one of MyHome.ahx or Samples.ahx and see if you can control any modules that match the housecodes of your modules and see if AHP can control them. Once you have done that successfully, copy one of your backup files to the Active Home Pro folder, load that into AHP and make sure it can communicate with your system. If it can, upload it to the CM15A.
Good luck!!