Joomla Component to display albums with special custom fields

I installed three joomla-based websites.
The first one is something like a database using gallery 2 and the gallery-component for joomla to display all albums and pictures the gallery contains.
The second and third one uses data from the first website, but only showing special parts of it.
now i want them to show pictures from the gallery2-installation so i don't have to install seperate ones.
The problem is, how can i tell the gallery only to show albums with i.e. "test" in a custom field on the second site for example?

i already tried to build a own component that grabbes the data from the first db. but it is far too complex for me. so i hoped somebody here nows how to do that?

Please please ;)

[EDIT]
Here's an example how it should work:

Name ____ Custom Field
Album 1 _ Page 2
Album 2 _
Album 3 _ Page 3
Album 4 _ Page 2
Album 5 _ Page 2

PAGE 1: Shows Album 1 / 2 / 3 / 4 / 5
PAGE 2: Shows Album 1 / 4 / 5
PAGE 3: Shows Album 3

Ok?
[/EDIT]