How did the install of GD fail? Did the compile fail, or did something like just one of the tests fail? If it was just some lame little test that failed then you probably got a message like "will not install without force", in which case you can go into your .cpan directory (or whatever dir you specified for building modules) and do "make install" so as to forcibly install it. Of course, if it broke at some earlier stage it may have been because you're missing some other program/library for which it is a wrapper, in which case forcing an install is decidedly not the right thing to do.