So there are 2 issues. One the way the package check is being done for libusb is failing to expand. The other which is probably easier to fix, but not one I know how to do, is to make it so the build can specify which libusb he wishes to use at configure time. With the latter I simple command line option of --use-libusb=/opt/local/ would solve all the hand edits I have to do. Fixing that might also solve the expansion failure, but all I can do is test at this point.