Luis,
I've managed to go through this list and make all the changes that I knew how to do and didn't require much research for me. Here is a summary of what I have done, with the git commit to the fsbv branch:
9d1d5b5 Rename system to cffi-libffi, add restart to default *foreign-structures-by-value*
95052e5 Use hash table for libffi-type-pointer
4b5d7fb Moved slots-in-order after foreign-struct-type, clean up libffi-*.lisp
953fbaf Fix conditionalization syntax in cffi-fsbv.asd
cc73a6f Add Windows grovel file
1ff74af Eliminate package cffi-fsbv, put :sizet in keyword package
Do these changes address your concerns? Can you test?
Thanks,
Liam