Effects are really great, and they make a map look cool, but in my personal experience they are detrimental to gameplay. They tend to either make everything too dark or too bright, and none are subtle enough to be used well without causing problems for people who have brighter or darker televisions. And they contribute to framerate lag because it loads every object TWICE (which is a pain on processing power.) I'd definitely say you should go without them. Of course, if its not playable or you are doing it to impress your friends, etc, I would go ahead and use them because it makes the objects look much nicer.
Just made a perfect remake of my favorite Halo ODST map "Windward". Need testers to test the gameplay !!
If you mean signiture, then you should try clicking this link. If that doesn't work, lemme know. Theoretically it should automatically go to your signiture editor, but I linked it from my own so an error may come up.