the fallout2 mapper? well you place out a critter, select it (if your having truble with selecting stuff, try to press the * button on the keyboard u then get this brown aiming cursor like when you use steal or lockpick on the skilldex ...remember to have numlock on) after uve selected it, you pres the up and down buttons on the bottom middle of the screen, now that should help, didnt it
by the way, when youve selected them u can also edit them by pressing the edit button on the toolbar u can give'em weapons and armour and stuff