Unreal Engine 4 is available for Win10 UWP app dev now

Hello! Can anyone help with small but very important problem with ID@XBOX project?
When i’m eneable OnlineSubsystemLive - all needed things working fine (achievements, save games and Leaderboard).
Save games saved localy, but saved and can be loaded. Without roaming data.
When i’m enable plugin UWP Platform Feauterse - achievements still working fine and leaderboard working fine, but save games cannot be save or load.
What can i do? Engine version 4.19.2 release uwp. Visual studio 2017.
Sorry for bad englesh and thank you!