I wanted to add several directories full of clip art to the available galleries.
I managed to (painfully) add the first one but failed to add any others.

From any OpenOffice application call the gallery menu by clicking the gallery
icon. Then,

Adding the first directory:
---------------------------
Click "New Theme," give a name "Alphabet," click the "Files" tab, select the
path to the new directory, click "add all." Voila, the new theme appears to have
been created ... but as soon as I click "alphabet" to see the new available clip
art I get the following error in a pop up window,

  An unrecoverable error has ocurred.
  All modified files have been saved and can
  probably be recovered at program restart.
Once I restart the program and click on the gallery icon, my new "Alphabet"
theme is not there anymore. However, I managed to finally add it by going againg
through the steps above and exiting OpenOffice as soon as the new theme was
added. Now, when I start OpenOffice, the "Alphabet" theme is there and seems to
work well ... but,

Adding the second directory:
----------------------------
With "alphabet" there, as soon as I attempt to add a second directory of clip
art I get the same "Unrecoverable error" as before. I haven't found a way to get
around it, OpenOffice consistently dies right there.