It happened because in order to activate LED Event Notifier you didn't have to install neither the MAG's system-ui nor CODeRUS's T-1-1 (for Inception) or T-1-2 (for Open Mode) tweak, but the Coderus Unrestricted System UI: T-3-1 (for Inception) or T-3-2 (for Open Mode) tweak. Obviously you must uninstall MAG's system-ui before installing Coderus Unrestricted System UI, then you can install the LED Event Notifier via T-3-1-1-10 (for Inception) or T-3-1-3-10 (for Open Mode) tweak.