Hello,
I apologize for the multiple value return confusion during my talk last night. If anyone is interested in the details and how we arrived at the implementation, there is a thread from the Parenscript mailing list that explains everything (two links because mailman broke it up):
http://lists.common-lisp.net/pipermail/parenscript-devel/2009-October/000639... http://lists.common-lisp.net/pipermail/parenscript-devel/2009-November/00064...
Happy hacking, Vladimir
PS - Here is the C to Common Lisp compiler I am working on: https://github.com/vsedach/Vacietis