$VULCAN/setup.scm defines the global variables of the system. These variables specify among others the host and port where the system will contact the different servers it uses.
Since the wheelchair and Flat use the same code, be sure to specify that you are using the wheelchair. In order to do so, include
(define *use-wheelchair-client* #t)in
$VULCAN/setup.scm. Next we explain the different variables have to be specified in this file.