Before using the vision libraries you must compile the C libraries in the Clib directory. There is a Makefile.SH in each subdirectory. You will need to make sure that the parent directory for X11/includes is defined or included in the make file. Then place the archive produced in each subdirectory in the directory $EIFFEL4/library/mel/spec/$PLATFORM/lib. This will need to be done on for each platform you will be running mel on.