I can't help you with 'machine', but keep in mind that Quickbooks for Mac and Quickbooks for (not Mac) are radically different. IIRC, there is/are plug-in(s) that link Quickbooks for (not Mac) and FileMaker Pro.
I blame it on #intuit.
p.s. I'm an x-plat kind of gal, so I want everything to be EQUAL.
Windows 8 does work with FileMaker Pro 12, but it is not officially supported by FileMaker. With that said, you may run into some issues with FMP and/or the plug-ins.
Keep in mind that all Intel Macs can run Windows, either natively via Bootcamp drivers or via emulation like Parallels or Fusion.