Picasa LightBox is a WordPress plugin that lets you easily add Picasa images to your WordPress posts and pages.
Once you have the plugin installed and activated, go to the Picasa LightBox options page and set your Picasa server (usually http://picasaweb.google.com) and your Picasa user name. Then set your thumbnail size and click Save Options.
Tip: If you want to import pictures from public albums other than your own, you can! Just enter any Picasa user name here and you should be able to pick photos from their public albums.
Create a new post or page. It is recomended to save your post before inserting pictures. This way, Picasa LightBox can get the correct post id and pass it to the LightBox plugin. Just click the Save and Continue Editing button.
Near the Upload tab, just below the Publish button look for the Picasa Photos tab and click on it. You should now see your Picasa public albums. If you can't see them, check your settings on the Options page.
Click on the thumbnail of one of your albums and you should see your pictures. When you click on a picture a new layer appears over it, allowing you to select the size. Once you clikc the desired size, the HTML code is inserted into your post or page.
To go back to your albums click the Back to albums link.
Thanks go out to:
Michael Toppa for his Shashin plugin: http://www.toppa.com/shashin-wordpress-plugin I used his rss-functions-mod.php file.
That's it. Enjoy!