I removed the qml cache for the app at .cache/QML/Apps/ubuntu-system-settings/ as suggested.
This appears to have cleared the fault - I've tried all the sub-levels which previously crashed with various changes therein.
Also have closed / opened the app several times between changes and rebooted the device.
System settings now running normally. Many thanks for your help.
Regards --
I removed the qml cache for the app at .cache/ QML/Apps/ ubuntu- system- settings/ as suggested.
This appears to have cleared the fault - I've tried all the sub-levels which previously crashed with various changes therein.
Also have closed / opened the app several times between changes and rebooted the device.
System settings now running normally. Many thanks for your help.
Regards --