Event log alarms have been set-up as per the documentation but i don't receive some event based alarms
You need to bring back ALL the event logs back to the server that you intend to alarm on OR none of the event logs back to the server for alarming to work. You cannot bring some logs back and not others.
Assuming this is your monitor set configuration.
All logs being brought back
No logs brought back
Some but not all logs brought back to the Kserver
In this case you will not receive any event log alarms for "Warning" events you are monitoring for.
Change your configuration to a valid one