Surface Laptop - Windows 10s only. Yes, only support for Windows Store Apps.
other surface devices which have other version of Windows 10
That page you link to shows the following:
Windows 10 S
Prefer to run non-Store apps? Easily switch to Windows 10 Pro for free until Dec 31, 2017.3
Introductory offer: Includes 1 year of Office 365 Personal5
... So no probs running full Windows 10 and therefore FileMaker on it :-)
I did not see any other options, than Windows 10 s yesterday, after reading skywillmott post, I searched again and found where it states it will run Windows 10 pro. Surface Laptop - Microsoft Store It's located on the Tech Spec sheet.