Addind solution that worked for me for this issue.
Started to appear for me after recent Windows Update.
Requirements: error that Mfplat.dll is missing while running “Color Basic-D2D” in “SDK Browser (Kinect for Windows) 2.0”
Solution: install Media Future Pack
Issue: I have Windows 10 N version. Media Future Pack is not installed by default for the N version. After Windows update I think it got deleted or something.
Installing Media Future Pack fixed Mfplat.dll error, after that Driver4vr started to work normally.
I already had issue with Mfplat.dll in the past that caused me to crash in any VRChat world with any working VideoPlayer, but I think it was before I got Driver4vr.