Failed to import on ByteProperty? Console Variable is Read Only?

I’ve tried to create a basic Settings menu to save graphics settings for my project based on this tutorial: Unreal Engine 4 Save and Load Graphics Settings using Blueprints Tutorial - YouTube
My only problem is that it doesn’t work. It creates the save file, but reads the wrong parameters. I’ve checked the message log and I get these errors:

Error /Game/GA/UI/VideoSettings : Failed import for ByteProperty /Game/GA/Saving/GraphicsSettings_Save.GraphicsSettings_Save_C:Res
Error /Game/GA/UI/VideoSettings : Failed import for ByteProperty /Game/GA/Saving/GraphicsSettings_Save.GraphicsSettings_Save_C:AO
Error /Game/GA/UI/VideoSettings : Failed import for ByteProperty /Game/GA/Saving/GraphicsSettings_Save.GraphicsSettings_Save_C:GI

Currently, my save game contains only 3 Enum variables called Res, AO and GI, which contains these:

Res:

1280x720
1366x768
1440x900
1600x900
1680x1050
1920x1080

AO:

Off
SSAO
DFAO
HBAO+

GI:

Off
DFGI
VXGI

I’m using UE4.9 with Nvidia Gameworks.

This isn’t my only problem. If I try to toggle DFGI via Console, I get this error:

Error: r.DistanceFieldGI is read only!

Is there any way to toggle it via Blueprint? Or can I access the config inis with Blueprint?