Fatal Error: using different user agent

[Essie]

I am really out of wits here. Since the beginning of the year, I basically set up a protection on my coppermine folder to only limit members who sign up for membership to access the gallery. However, I did set out special privileges for specific search engines to still be able to index my gallery by modifying the htaccess file within coppermine. For some odd reasons, the same codes that work at my other subdirectory folders do not seem to work with the coppermine.

I know that it's not working because when I test it using a different user agent, I realize I get a blank page with "Fatal Error:" msg on it. But when I set my user agent default, I am able to view the gallery. I did not notice this problem until I found out all the major search engines that indexed my gallery ended up with "Fatal Error:" msg. I think within coppermine script, the developers must have put some "bad behavior" codes to recognize and flag this msg. I like to know what I need to do to allow my gallery to be accessible by other search engines from my modification of the htaccess.

I know this has nothing to do with me setting up the gallery as protective folder because when I removed the source code within my htaccess, I still get the exact same problem. So this is a problem within the gallery script itself. Any ideas?

Sorry, I cannot give out my direct url link in public due to security reasons. If I can send a private email to the developer, then I don't mind disclosing my direct url link. Thanks in advance.

[Essie]

I forget to mention that I am using the latest Coppermine gallery version and that the only plugin that I use for this script is the watermark. Nothing else.