Thanks for your prompt reply. I did have a try using the design() command, e.g, design( "myLib" "mydesign" "schematic" ), but I kept getting an error stating that "currently you cannot specificy a lib-cell-view with the design() command in ocean". This obviously contradicts the information provided in the Ocean reference document. This is exactly what I would like to be able to do though, just define the cell in the library rather than the netlist itself.
If you have any further thoughts, I would be very grateful. In the meantime, I will re-post this question in the Custom IC section as you suggest.