Question: When I click on a picture I get a 404 error.
Answer: Check and see if you have any "file extension like" tags on the end of your image titles. You can take the extension off the image title as a quick fix (you don't have to do this), but the problem is probably in your .htaccess file. I am not the right person to be talking to about that as I am no expert. Here's a
link for information on setting up .htaccess for opensef. If this doesn't help you fix your problem ask for assistance from these guys as they are gurus of .htaccess.
Question: When I click on any picture all I get is the first picture in the gallery.
Answer: You have "All Lower Case URLs" set to "Yes." Change this value to "No." This may not be the only problem causing this to happen but I have seen it fix this issue.
Question: I have upgraded to RC3 and now I don't see my pictures.
Answer: Turn of the hot link protection in zOOm Gallery settings.