In "Table 5.2.1 User Account Configuration" there's a row:
Microsoft Account / checkbox / Set if the user is connecting from a Windows 8 or higher system
This is a bit misleading. It implies that that checkbox must be set if the user uses Win8+. But as best as I can tell from the forums, it's only necessary if you use Microsoft's 'cloud' accounts as apposed to local computer accounts. The UI's help text is a bit more elaborated, but could be clarified too.