FTAnalyzer is a program I've written as a personal project to help my own research. I make it available free for the world to use. It has features that are useful to Lost Cousins Members and Lost Cousins Members have helped make the program better by suggesting new features and testing existing ones. However it is just a free program available to anyone it is not specific to Lost Cousins in any way.
The reason it may not work on a Mac is that I don't have a Mac so there is nothing at all I can do to test it. Whether there are lots of Mac users amongst Lost Cousins Members or not is, I'm sorry, entirely irrelevant. I produce the program free of charge in my own time using my own resources as a benefit to anyone who wants to use it world wide to help in their family history research. It is NOT a commercial venture and as such Peter and Lost Cousins specifically cannot be blamed for it not running on a Mac. Due to the many features that specifically help Lost Cousins Members in the program Peter has been very supportive of the project, however any faults or issues are entirely mine no blame can be attached to Peter or Lost Cousins.
The program can be made to run on a Mac but needs a program called Parallels or Bootcamp to make it work. However because I have no Mac I cannot test it on a Mac so I cannot support it on a Mac. The unfortunate issue is that Apple specifically require developers to pay them to develop software. On Windows you can develop applications free and make them available free to anyone to use. On Apple products you have to buy a physical Mac and the development software. Then write the code specifically for a Mac. It wouldn't be the same it would need entirely different code, which would double the workload. This is typically why you get so much less software available for purchase on a Mac. Larger companies can of course afford to develop for a Mac. As a solo developer I cannot afford to do this especially when I do not have and do not wish an income from the project.
I hope this explains the situation somewhat better.