After transferring the site to a new host, most stuff appears to be functioning correctly. One problem is this error log warning every time a page is loaded:
Only variable references should be returned by reference in /.../cgi-bin/links/admin/Links/PHP/adodb/drivers/adodb-mysql.inc.php on line 423
The bigger problem I discovered is the Jump links don't work.
PHP Fatal error: Call to a member function fetchrow_one() on a non-object in /.../cgi-bin/links/admin/Links/PHP/Jump.inc.php on line 120
I'd much prefer salvaging the old install rather than upgrade to the new one, if at all possible. Integrating a CGI script into a PHP site and templates is never fun.