You cannot control things withing PaperUI (or anywhere else for that matter) until you move the Items out of the Inbox. Then if you have turned off Simple Mode under Item Linking then you must create Items and link the Channels of these devices to those Items manually. With Simple Mode turned on, OH automatically creates Items for all of your Things and Channels.
Finally, deleting /var/lib/openhab/userdata/cache and /var/lib/useradata/tmp will clear out most of the old stuff. Deleting all of userdata will clear out everything and make it as if you just installed OH.
I am aware that I can neither control nor directly map things. My issue is, that PaperUI used to display values of all added things. Now it only displays the things, but shows no values.