Microsoft have released patches for the App-V client built into Windows 10 build 1703 and 1709, as well as one for App-V 5.1 (Hotfix 11):

The major headline for the Windows 10 patches is reverting the registry system from the new container-based system (CREG) back to the old virtual registry system (VREG). This should resolve a range of reported issues that crept in with 1703. All 3 patches also contain a fix to prevent registry corruption under HKCU when using connection groups, so it’s recommended to update as soon as possible!