BOM Custom Part Number

I have been working on a name and coding system that use the custom property tab. This is all good and is working well The problem comes with the BOM as the part numbers are made up of many custom properties. I'm well able to link one property but I can not work out how to link multipale property with out getting any errors.

Any help with this would be great as I really do not want to start the coding system all over again.

Regards,

James

SolidworksBill Of Materials