There isn't much to this kit, just four pieces, two "rafters" and two roof pieces. I think this is a problem because of the length. The knuckleduster buildings are the longest buildings currently being produced that I have built. It took a lot of work to get a good glue joint in the center of the roof because there was nothing to support it.
I really struggled to get this roof together properly. I'm sure the second will go together easier. I pulled out my magnet jig for this. After I glued the rafters in place I noticed that I wasn't getting a good join in the center. I put the roof flat against one edge of the jig and then use the magnets to hold it in place (these are really strong magnets). I was then able to use my steel weights to hold the roof down till the glue dried. A third "rafter" in the center would have corrected this problem and would make for a stronger roof.
Here are the construction pictures