After about 5 yrs I finally got a great record session that works perfectly. I am running 3 trains, one passenger, one freight and one very short train headed by an H10 with one boxcar. It lasts about 10-15 minutes. The layout is about 6x11 with two interconnected loops, 5 switches and a Z1000. The Z1000 had NO problems with 3 smokers going, 4 lighted pass cars, one lighted caboose and the switches running off track power!! My point is practice using the Record/Playback part of DCS it is absolutely amazing!!
Hint: Leave some extra room for activating switches etc. Stick with at least one foot of free space if not 18".