Icecream man forge

I have created a kiddy lane map on halo 4, But I am having trouble with the settings for it. This is what I have tried; I set it up as an infection game, one infected rest regular, one life a round. There is two things I am having problems with one setting up a powerup (I literally can’t find it or find where to give it it’s traits), then also when I start the game some times the infected spawn outside the kiddy lane (not in created area) and the non infected inside the box where the warthog is. I need and would appreciate all help, thanks in advance.

Also I created map inside the grif ball map variant.