Hello Gareth, I too have been using Osmond and DesignWorks (both are OS X now). I use an old PC program (Metalman) in Virtual PC to do my sheetmetal design, DXF out and into VW to get the parts to fit on the PCB and the connectors to line up with the sheetmetal, then convert the parts on the PCB to lines and DXF out and in to Osmond, build a library of the parts I used in DesignWorks and finish the board in Osmond.
Must be an easier way, but I haven't found it.
Don