Questions about the Heroes 4 map editor.

Sorry, I'm new to mapmaking. I have a problem... I created a map, and everything seems to be okay. But I think I'm setting the victory and defeat conditions incorrectly. (Defeat - if a specific hero dies, and victory - if a specific artifact is found). It seems like I set everything up correctly, but when I play, the game doesn't end in either victory or defeat... ((( What could be the problem? I set the conditions using "conditional actions" in the "placed events" section, and I've also tried other options....
And what are trigger events?
P.S. I'm using The Gathering Storm.