Glad to hear from another person who visited Minirama! I was there in 1963, 1968 and 1969. Took pictures in 1968 & 1969. I am always looking for other peoples pictures they took at the attraction; be they slides, or movies. You are right about the staging area in the back. The trackage was 666 feet, and a continuous loop. There were seven trains in the 30 minute program, and as you say they advanced through the staging area and then came out into the diorama from the right. At that time the sound effects and speech for each particular train would come on via continuous loop tape players. When the train left the diorama it again wound it's way around the staging area, and this time, would enter the diorama from the left, and silently traverse thru the diorama, and then the process started all over again as the trains entered correctly from the right
Anyone with pictures could sure contact me if they wish. And anyone knowing the whereabouts of the Dells Boat House, Hydro electric plant building, or the interesting bridge, I'd really like to track these items down. Always looking for B&W postcards, bumper sticker, etc.