Placeholder to add album artwork missing in playlist

Even though I added artwork to an album manually, it does not show up in the itunes playlist (although it shows up in the GET INFO window). I've noticed that if there is a "music note" placeholder, I CAN add artwork and it will show up on the playlist, but if it doesn't have a placeholder (top image - see difference of 3 placements), it will *not* show up in the playlist even if it is listed in the Get Info page (see second image). How can I get my image to show up when there is not music note placeholder?

1. MIssing placeholder on Top Album:

2. But same Album *is* showing in Get Info window: