I have created a new AutoDJ account and import only 10 songs for testing.

I would like to show the album image so i create 10 images like you mention in Documentation for Albums with Folder images.

Assuming i have "BANANARAMA - VENUS.mp3" and the image "BANANARAMA - VENUS.jpg"

In Media Library shows the default image.

When i click Re-Index album nothing happens.

I search in the forums and find that i can re-index all my media folder with one command :
/usr/local/centovacast/bin/ccmanage reindex djpro_disco --updateall
Result = OK Tracks reindexed but nothing changed in the Media Library.

Also i have found the command :
/usr/local/centovacast/bin/ccmanage serverdiagnostic djpro_disco getalbumdata --file="BANANARAMA - VENUS.mp3"

Result =
[DBG] Performing lookup for artist "BANANARAMA", title "VENUS", album "VENUS", for account 10
[DBG]   Not found in cache; dispatching request to driver folder
[DBG]     Driver returned: image: "BANANARAMA - VENUS.jpg"
[DBG]     Resizing image BANANARAMA - VENUS.jpg...
[DBG]       Driver error (folder): Could not resize cover image file: Image daemon request failed: failed to open stream: HTTP request failed!
[DBG]   Not found in cache; dispatching request to driver embedded
[DBG]     Driver returned:
[DBG]   Not found in cache; dispatching request to driver custom
[DBG]     Driver returned:
[DBG] Final result:

What next ?

This means something is wrong with cc-imaged (the daemon responsible for resizing/cropping the images).  If it's a one-time thing, simply restarting Centova Cast will fix it.  If it happens regularly, please open a ticket with the helpdesk and we'll be happy to help with this.