As far as I can tell, the (remove) form simply returns its second argument
instead of doing its job.  Test case attached - this will fail regardless
because of the lack of terrain types, but it'll also give an error about
trying to match a length-7 list with another list that should also be
length-7 but is in fact length-10.  The only shipped game module using
(remove) is tailhook.g.  I haven't figured out whether (remove) is
misbehaving in that file, but it definitely misbehaves in my test case.
-- 
Matthew Skala
mskala@ansuz.sooke.bc.ca                    Embrace and defend.
http://ansuz.sooke.bc.ca/