Make sure that you haven't denied access for the robot using one of the supported methods (robots.txt or meta tags). Apart from that, google might consider your content not to be worthy to be spidered. Since only Willow left his URL, I can only guess if this is the case for you as well. The issues with Willow's site are that he nested his category/album structure very deep, which means that the google spider needs to follow many links. Additionally, there is very little textual content, so in terms of search engine friendliness, you should add a balanced number of keywords, title and description for the images. Willow's domain redirects to the IP address (the URL he posted redirects to
http://87.106.18.130/), which is very bad in terms of search engine friendliness and probably a result of cheap webhosting or self-hosting. Google doesn't "know" the domain at all (
http://www.google.com/search?q=site%3Afoto-friends.de returns zero results), the IP address (
http://www.google.com/search?q=site%3A87.106.18.130) returns just 121 results and has a page rank of "2", which is not surprising at all.
As the regular google bot doesn't consider the site worthy to be spidered, the google image bot will of course only spider a very small number of pics as well.
I can't tell for the rest of you who posted on this thread, but only for Willow: you haven't understood the basic concepts of search engine friendliness - this is not related to coppermine, but to your reluctance to do the basics in SEO.
The only thing that relates to coppermine is the fact that all the alternative navigational stuff (the meta albums etc.) result in a lot of double content, seen from the spider's perspective, which currently only can be circumvented with manually adding nofollow tags to the meta album links. This has been discussed in similar threads already. But before you try that, do the basics first.