Hyper Rails Help?

hey, im building a hyper rails coaster that i think is really cool. but i want to be able to run 2-3 trains at 1 time. is that possible on no limits? and if so how? because whenever i put in 2 trains, like type in number 2 for number of trains it says number of trains no longer total block or something like that. also how do you do screen shots? thank heaps. seeyas.