Gallery2 image buttons missing from the your rich-text editor ? I'm sure this is relevant to the other CMS', Joomla and wordpress.
From the drupal issues queue http://drupal.org/node/300305
http://drupal.org/node/350100



Locate the wysiwyg_tinymce_plugins function in tinymce.inc

in Drupal 6 it can be found in /modules/WYSIWYG/editors/ or /sites/all/modules/WYSIWYG/editors/ at line 373 in the 6.x-2.4 d6 module.

Insert the the g2image array as follows:

function wysiwyg_tinymce_plugins($editor) {
  $plugins = array(
  'g2image' => array(
      'path' => $editor['library path'] .'/plugins/g2image',
      'buttons' => array('g2image' => t('G2 Image')),
      'url' => 'http://g2image.steffensenfamily.com/',
      'internal' => TRUE,
      'load' => TRUE,
    ),
    'default' => array(
      'path' => $editor['library path'] . '/themes/advanced',

Add G2 button to tinymce in Drupal 6; Admin:Site Config:WYSIWYG