If you have installed from mer-obs, and Store offers you an update, it is possible that Settings app will stuck with install-progress spinner, and you can not access it.

This can be fixed or/and avoided by uninstalling* mer-obs version, and then re-attaching TOH part and allowing it to install from store.

*) either pkcon remove harbour-ambience-tohkbd2
or go to Store -> my apps -> tohkbd2 -> Uninstall