2)
Trigger(6,'qaz','qaz') - activates a trigger with the name 6 (REGION_ENTER_AND_STOP_TRIGGER) on the map. You need to write this command simply at the beginning of your script (not inside a function).
==
Trigger(6,'qaz',nil) - resets the trigger (after this command, it will no longer work). You need to write it inside your function when you want the specified region to stop working (calling the function).
==
function qazF (heroname)
if heroname == "Metlirn" then
CreateArtifact(54, 54, 20, 10, 0);
Trigger( REGION_ENTER_AND_STOP_TRIGGER, "qaz", nil );
end;
end;
Trigger( REGION_ENTER_AND_STOP_TRIGGER, "qaz", ''qazF'' );
==
This should work.
And also - check if the region name matches what you created in the editor.