Flexkiller

Do the things that are not working have something in common?

I had the same issue: Remove enbhelper.dll in the enbseries folder, don't delete it just place it somewhere else for the time being, now start up skyrim and you sould now be able to make the changes you want. If you're done just move the enbhelper.dll back into its original position and you're good to go :P

Are you using ENBHelper?