That's because in newer versions of HA GUI part of this component doesn't work and is disabled as mentioned here.
You can either use it with older version of HA or (if using any version of HA) use MQTT to control it (although it cannot be compared to GUI, I know).
I manually installed it and also tried installing it using HACS. I cannot see the Alarm integration at all
there is no error in the logs. Cleared cache and tried other browsers.
Please can someone help.