GC 1.5 is installed & working, but orders are still not showing up in Admin. responsehandler.php opened directly returns the error:

Fatal error: Call to a member function on a non-object in /home/mpayson/public_html/zc137/includes/languages/english/credit_cards.php on line 57

That error doesn't appear to be mentioned in any other post in this thread. That file has not been edited in my install. Here is line 57 for reference:

Code:
define('IMAGE_CC_ENABLED_VISA', zen_image($template->get_template_dir('cc1.gif', DIR_WS_TEMPLATE, $current_page_base,'images/icons'). '/' . 'cc1.gif'));
Since I don't accept credit cards directly, I can't imagine why this is even being called. No additional payment modules are even installed.

response_error.log reports:

Sun Feb 18 0:23:46 EST 2007:- Shopping cart not obtained from session.

Please forgive me for not reading through the entire 68 pages of this thread before posting. I've read many of the posts, particularly from around p32 and through p49 to this point (plus roughly p60+). Based on the recommendations on those pages I've upgraded from 1.04r to 1.5, but I'm still getting the same error. I'll keep reading through the rest of the thread, but if anyone has any suggestions in the meantime, I would really appreciate it.