This V-1 Launcher originally started as the very basic plastic model from the FOW Open Fire! boxed set. It's a good model but the launch rail is really lacking in correct details.
First, I added a "concrete" base made of thick plasticard, sized at the platform to not only accommodate the crane and pressurized launch cart but also to double as an objective for FOW games. I then added some styrene strips to the launch rail to enclose the ends and add the circular pipe for the pressurized launch cart. Last, I added the launch cart, crane, and ladder from various styrene shapes.