They are but they do not market it. If you look at the webpage and click on the PAF Page you will see they list it there. Companion was first devloped for PAF and now is available for other SOftware as well.
Here is a copy of an email from them regarding a bug I found.
Dear Mr. Carpenter:
There was awork around to reduce the total memory to just under 2 GB, so you may not have to reduce it by quite so much.
The problem surfaces when the amount of RAM combined withVirtual Memory is 2 GB or greater.The memory issue will be fixed in the next release of PAF Companion. For now, the solution is to reduce your Virtual Memory until the total RAM & VM is just under 2 GB (1999 MB)
To do this: 1. Right Click on "My Computer." Select Properties. 2. Select the "Advanced" tab, click on the Performance Options button. 3. Check the amount of memory allocated to Virtual Memory. Reduce as required.
As to when the next release of PAF Companion will be available, you would need to contact Dennis Meldrum at MeldrumDL@ldschurch.org for that information.