The mechanical design studies focus on two areas. The first is the design of low-mass silicon vertex and tracking detectors. The second aspect of the studies are the machine detector interface issues between the vertex detector and the beamline elements. An inital design of an outer silicon tracker for the Silicon Detector for the ILC has been completed. Current efforts focus on the design of a vertex detector, together with a design of the beampipe.
To date little documentation is available in the form of write-ups. A good overview can be found in the presentation (pdf) at the ECFA Vienna Conference.