Greetings! I have not tried it, but I know handling things by large buildings can be a problem, as the focus wants to be on the building itself. I would assume you have to place the locomotives onto the track outside the shed and then either use the move setting to back the locomotives into the shed, or perhaps even go to Driver mode and drive the locomotives into the shed. If it is a small one or two track shed and does not have its own track, you may be able to lay the track and place the locomotives before your put the shed over them, but that is not going to work for a large roundhouse made up of lots of pieces. Best of luck and I hope someone with more experience will answer!