Upgraded to NPVR 4.2.4. Now in Video Library there is no folder art only a white folder - the fanart still shows as the background image.
I use Media Companion to generate all the art for each show in box sets - Show poster in the Upper Folder, Season Poster in the Season Folder etc. all stored as folder.jpg - Worked well until today.

If you need logs I'll have to wait a few hours to get them.