Oh, now I understand, we have more views and it was not clear which do you use.
This view is called "List (by Album)", I have added request as issue here: https://www.ventismedia.com/mantis/view.php?id=18062

"Subview" I call view with info about specific album/artist/genre. You can open e.g. album view by clicking album title in Summary column of "List (by Album)" view, artist view by clicking artist name. It is accessible also from other places, like double-click on image when Albums or Artists are displayed as grid.

I have a view that shows Genre, Date, Artist and Album at the top and in the panel below these it shows the album art, summary, track listing with several track columns. In MM4 when I click the album art in the lower panel it clears the playlist and plays the albums tracks. In MM5 it changes the the album info in the Playing panel and that's it....it [b][u]doesn't[/u][/b] clear the playlist, start the queue, etc. like it does in MM4. I thought that's what the Options / Player controls were setting.

I know i can double click on the album [b][u]title [/u][/b] to clear the playlist and start the album but I found it "easier" to click on the album art as it is larger than a row of album titles in a list (and to me more intuitive).

I don't understand what is meant by a "subview" mentioned by MiPi but if this is a new feature I don't care for it (yet as i don't understand it maybe).

If you mean double-click in Albums view, it opens subview - view for selected album (or Genre view in Genres, Artist view in Artists). It is new feature of MM5, it was not in MM4. If you want to play album, just open context menu - Play now.

Do you mean in "List (by Album)" view ?

MM5 differs from MM4 for the Default Action and Play now action in that when I double click on the album art in MM4 the play list is cleared and the album is started. Using the same settings in MM5 it will not clear the play list. MM5 will not doing anything other than select the album in the list and show the album art underneath the playing list but won't populate the playing list and/or start the album. Is this a bug perhaps?