In his design Alfonso made the CM connecting to the SM by clamping it with the umbical. I wasn't certain this would work well...
I used 2 small magnets for connecting. Problem was to get them on the proper distance. There I followed this method: I added an extra blukhead (disk) which in the center got one magnet. This disk could freely move in the SM-body with little space. The other magnet was glued in the center of the CM-heatshield. In the top-edge of the SMbody I droppeed some dots of glue. Next I put the CM on the SM, turned it over and the magnets attracted eachother. The disk reached the gluedots and was set in place. After drying firmly set with some extra glue. See the drawing...
I hope this explanation was clear...