[Solved]: Can't update Gallery Configuration

[gloda]

URL: http://lgspeiteng.com/foto/
Configuration: Coppermine 1.4.10 with Modpack v1 (stable) and bridged to phpBB.
Server: PHP4&5, MySQL 4.
System: Mac OSX 10.5.7, problem occurs in both FF 3.51 and Safari 4.02.
Read: the doc, faq, board rules, searched and found http://forum.coppermine-gallery.net/index.php/topic,60206.0.html and http://forum.coppermine-gallery.net/index.php/topic,16356.0.html neither of which got me very far.

Problem: I can log in to the gallery, use it in admin mode, upload photos. I can access the Config panel and adjust the settings. Once I click "Save new configuration" however, I am taken to http://www.lgspeiteng.com/foto/admin.php which then consists of a page which holds two fields and an "authenticate" button. Here's the souce of that page:
<form action='/foto/admin.php' method='POST'><input type='text' name='login'><br/><input name='pass' type='password'><br /><input type='submit' value='authenticate'></form>
(screenshot attached)
Regardless of whether I enter correct or incorrect login data, clicking authenticate changes the site, it then only says "Powered by Coppermine Photo Gallery Modded by Stramm" and displays the list of available languages. (screenshot attached) Picking a language (tested with German, English and Luxembourgian (custom translation)) gets me back to the Gallery Configuration page on which the settings have not been updating with the changes I made before saving.

Other info:
-The gallery used to be installed in the folder /cgp1410 before I renamed that folder to /foto some months ago. The new URL is registered correctly in the General Settings/URL of your Coppermine gallery option.
-I don't know if the following problem is relevant for / connected to this issue: I cannot log into Coppermine unless I log out of phpBB beforehand. If I'm already logged in to phpBB clicking Login in Coppermine just takes me to the forum page, but returning to Coppermine I'm still logged out. If this issue is not connected to the problem I'll try and resolve that separately.
-The /foto folder is chmodded to 755 and the files in it to 644.
-The problem is new, i.e. I used to be able to change the settings. I don't know if I have successfully changed settings after renaming the folder from /cgp1410 to /foto. The renaming is the only change I can think of that has happened since I last edited the Gallery Configuration.

Please help me resolve this issue so that I may update the settings of my gallery to my current needs. If there is any other information that I can supply in order to facilitate support please let me know.

[Nibbler]

Your gallery was hacked because you failed to keep up with security updates. You need to sanitise your gallery as described in http://forum.coppermine-gallery.net/index.php/topic,51927.0.html

[gloda]

Nibbler, thanks for the swift reply. I shall work my way through the documentation and report back with my results.

[kuul]

I am not allowed to sign into my photos at kuulkreations.com/gallery - why?  It thinks that I am a regular user.  I can not go in and update my photos...not allowed to to go into admin side.

[Nibbler]

Locking. Stop spamming our forum.