Alerts based on UnDP

I have had a hard time configuring some Universal Device Pollers and creating alerts based on their status.

I am trying to monitor NTP and managed to create and assign a UnDP that retrieved the Stratum value of selected nodes.

The only thing that happens now is I get a graph that usually stays at 2-3, but might jump to 16 :-)

But I need an alert if the value exceeds a value ( example 4 or reaches 16)

I have tried to create an alert based on custom node Poller, and other.

But it never gives me my UnDP as possibility when defining trigger condition