Yesterday evening we finally got the casings. There were some minor issues with tolerances but after some hours with a file and some soldering of cables we finally got the first two full OpenShoe units assembled:
The box is (including lid) 27.5x40.5x32[mm].
Really the assembly is not complete yet. As you can see there is no screws in the lid. Those, together with insets which will go in the holes in the box, we will hopefully get tomorrow. Currently we are solving the problem with some tape around the box.