OK, my opengl demo now runs via CFFI bindings on clisp/win32.
(a) I had to rearrange things so libraries get loaded during the ASDF build, before any bindings for said libraries do.
(b) The CLisp equivalent of Lispworks's make-pointer is unsigned-foreign-address, which was necessary to pass an enum as a pointer argument (odd Glut/win32 issue).
Congrats, I will now do a (favorable) Google mentor evaluation for CFFI-luis.