My frustration is that any photo I can find shows the exterior of the shikumen with no idea of what things look like once through that front gate. How big is the courtyard? How wide are the houses? (In the picture of demolished shikumen, they don't look much bigger than 12-14 feet, if that.) The Shikumen Open House Museum apparently has seven rooms somehow crammed into 367.2 square metres/ 1200 sq feet, but I can't get an idea of how they're arranged-- especially as there's no fig 1 or fig 2 that I can see on that webpage. Two floors of railway-type rooms, one opening out of another? Unlikely. A corridor somewhere? but where's the space for it? And essentially, how could rooms like this be partitioned up so that several families would live in what used to be the dining room? Floor plans is what I need, and can't find.
This blog at least shows you the rooms, which do look pretty small.