Unfortunately some Windows 10 style applications are tightly integrated within Windows and can't be blocked normally. You do have a couple options though:
1) Block all Windows 10 style applications, by adding these files to the "Apps" tab while editing a block list:
C:\Windows\system32\applicationframehost.exe
C:\Windows\system32\wwahost.exe
2) Uninstall the apps you want to block and then block the Windows Store app so that you can't reinstall it. The Windows Store app is listed under the "Win 10" tab as: WinStore.App.exe