See what you mean Malcolm. Never seen that before. Did you try the info button on the remote to see what shows on the B2 unit display?
How long have you had your B2 and have you ever updated the software? Asking as your screenshot of the UI show the wiggly line which doesn't show anymore on mine. Having said that in your settings the info on Software version HD capacity and file info is all missing.
Just seen Daniel has pointed out where the Scan Disk button is for you.
Don't think the guest mode should affect the stats, and the screenshot shows Source as Hard Disk paused. So it should be reading from the Hard Drive ok.
Make sure the B2 is doing nothing else and run the Scan Disk.
Once selected you can see the file numbers being scanned changing quickly near the bottom of the Settings & Status box where it says "Idle" before you start. Once completed it will return to saying "Idle" again. Close the settings box and re-open it again and see if the software version and file stats are there. The scan disk is supposed to update your music library if any changes are made.
See how that goes.