As of today the current 32-bit Windows version can load in ancient FileMaker Pro 7. We don't expect clients to use that, but from time to time, a client asks about an older FileMaker version. We highly recommend to upgrade to a more recent version.
As of today, we have about 21% of users with FileMaker 20.x, about 72% on some 19.x version and just about 6% on older versions.
For macOS we support currently macOS 10.13 and newer in FileMaker 14 and newer. If you need plugins folder older macOS versions or 32-bit FileMaker Pro, please let us know.
For Windows we support currently Windows 8 and newer. Some features require Windows 10 or newer of course. Please contact us if you need a MBS Plugin version to run on Windows 7 or Windows Server 2012 for some reason.
We also support the Claris Pro/Server line of products in case you use them.
And of course we work hard to get our plugin ready for the future. We usually test with future FileMaker versions in beta testing, so we are ready for any change long before the release.
Let us know if you have questions.