I downloaded the new version from the link in your post, it uninstalled 524 and installed 525 (yes 525 is shown in >About).
I tried again - opening Daminion, closing catalog etc... Daminion still tries to access the floppy drive when the catalog is closed, so I did the simplest thing and dis-activated the floppy disk driver - so that's fixed. However Daminion still opens the previous catalog when loading ... but please don't worry about that KM, it was just an idea for an option - the floppy disk problem WAS a problem !