Gnome control center deb package is broken at Byzantium, in other words you can change any gnome settings at least you use gsettings or dconf-editor manually, here is the output error:
adrian@puri:~$ sudo apt clean; sudo apt update; sudo apt install gnome-control-center
Hit:1 https://repo.pureos.net/pureos byzantium InRelease
Hit:2 https://repo.pureos.net/pureos byzantium-security InRelease
Hit:3 https://repo.pureos.net/pureos byzantium-updates InRelease
Reading package lists... Done
Building dependency tree
Reading state information... Done
61 packages can be upgraded. Run 'apt list --upgradable' to see them.
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:
The following packages have unmet dependencies:
gnome-control-center : Depends: libgnome-desktop-3-18 (>= 3.27.90) but it is not installable
Recommends: gnome-online-accounts (>= 3.25.3) but it is not going to be installed
Recommends: gnome-user-share but it is not going to be installed
Recommends: rygel but it is not going to be installed or
rygel-tracker but it is not going to be installed
Recommends: libnss-myhostname but it is not going to be installed
Recommends: realmd but it is not going to be installedE: Unable to correct problems, you have held broken packages.