I figured I'd wait until after the memory issues were reduced to a dull roar before reporting these idiosyncrasies.
After playing an album, the sidebar functions (albums, artists, files etc) won't respond anymore (won't open) to be able to select another album.
In addition the drop down list of options on the apple pull down menu (Media Center 18) (at the very top of the screen) ceases to function (it does change to the highlight color) as well. The 'File' pull down menu option in the MC window does function but is still showing Alt+F4 instead of Cmd+Q (⌘+Q)
I have to quit then re-launch MC, to bring them back to life.
Also after playing for a while when I switch views from the sidebar options, the column headings revert to the 'stock' preselected list. And when I then use a previously saved preset of my making, it won't always fully reflect my choices for what I saved.
JJ
ps this applies to x.x.156