GPC can be installed in two classic ways :
from binary packages
from sources
GPC works in a GNOME environment. This implies that the following libraries are neaded to correctly use GPC :
GLib/GTK+
GNOME
GDK-Pixbuf
A correctly installed PosgreSQL server is also required to store GPC informations, on the local machine or on a remote server.
GPC has been developed and tested with GLib/GTK+ 1.2.8, GNOME 1.2, GDK-Pixbuf 0.8.0 and PostgreSQL 6.5.3, running on a Linux machine with Slackware 7.0 (updated with some packages from Slackware 7.1) and a Linux 2.2.16 or 2.4.0 kernel. Older versions and other Unices supporting GNOME may work, but this has not been tested...
Last GPC releases (since 0.6) have been developed on my new machine with Debian GNU/Linux, updated with GNOME 1.4 Packages provided by Ximian