Trigger Infections

I was wondering if anyone else had the same problem. To break it down, I found that at random times, my maps will have a trigger malfunction and just stop working when it was working before from tests. Does anyone know why? The only thing I can think of that might affect it is when i create a new unit after writing triggers. Is this so? Any advice as to how i can avoid this in future situations would be appreciated. Oh and i don't use the test map funciton on map editor just in case anyone was wondering.

ps. Also if i save the units i created and create a new map. Will new triggers i make be infected? -Thanks

Yes, I've had something similar to this. I would make alterations to my map and a trigger would get disabled because it gets altered. I have no idea what causes this, but it's very annoying because I sometimes don't notice it until I see something wrong when testing the map out.
:(