Just a note that I have had JRiver MC since before 23 so I love most things about this but not everything!
I have discovered that MC 32 is not backing up my library. I had always assumed that JRiver was making an auto backup of my library but when I installed Windows 11 and it made my system un-bootable and had to do a fresh install ; I discovered that 32 was not actually making a backup; Luckily I had a backup from 28 (And all the way back to 24 -- I took a full image backup of my old system partition) so just lost some changes; then when I wanted to have 31 on my system as well (I need both, one to play back on my Ayer QB0 Twenty for music and another version for HDMI and Video), ran a manual backup as 31 does not seem to be picking up my 32 library; So figured I would take a manual backup of my 32 library only discover that even this did not work even tho MC 32 said it took a backup; it did actually create a backup directory but it is totally empty (oh the newly installed 32 did create a backup up in the 28 directory!
But my old library is gone forever as 32 never took a backup, unless somehow I can recover (use) the old library from my partition backup in C:\Users\YourUsername\AppData\Roaming\J River\Media Center 32\Media Center Library\