It's difficult to document as sometimes you think it's fixed but coming back to the album later will often display the problem again. I have never had an error report, so can't really supply a debug file (unless there's another way - if so, please let me know). All examples are for adding whole albums rather than individual files. I will experiment with editing properties for all individual files within an album to see what happens. I've tried to document, below, a typical evening trying to sort this problem. Please note, the screen grabs show 2 different albums but the problem is consistent within any given album displaying this issue, but it's difficult to keep up with the various problems and the Mushroom album seemed to fix itself (at least, temporarily, so I had to move to a different album for this example.
The following image shows the problem. The blank thumbnail has a path to a correct folder.jpg file and is exactly the same artwork as in the file tag above it.
The following image is how I would expect the panel to look after being fixed, but the folder.jpg image doesn't have a path! This image will disappear and show a blank after a restart.
If I scan the watched folder again, various problems can occur. The most common though is the example below, where an extrta piece of artwork creeps in. There are now 2 thumbnails (1 blank, one filled) with the same file path except the blank one shows no resolution. Looking in the folder will confirm there is only one folder.jpg
Next, if I delete the blank image and refresh the view (F5) a strange thumbnail appears, with filled artwork thumbnail, but with a strange path that doesn't exist and with dashes between the elements instead of slashes. Deleting that thumbnail actually produces an artwork file with a filename the same as the path with dashes (as in image below)
I have wondered if the MM4 database might have been corrupted or incorrectly read when installing MM5. I have considered starting from scratch but, apart from losing all my history of "Added" dates, I am concerned what MM5 might do to my real world files.
Hope all this helps. Please let me know if you need anything else and I will try to document it. Thanks again for all your help.