Thumbnail paths not created correctly

The thumb paths in the XML document had /files in twice. I rewrote the Format a Image function like this:

/**
 * Format an image.
 */
function theme_slideshowpro_xml_image(&$node, $size = 'preview') {    
  $output = '<img src="%src" title="%title" caption="%caption" link="%link" target="_blank" tn="%thumb" />'."\n";
  $variables = array(
    '%src' => slideshowpro_get_image_path() . basename($node->images[$size]), 
    '%title' => check_plain($node->title),
    '%caption' => variable_get('slideshowpro_title_as_caption', 0) ? 
      check_plain($node->title) : check_plain(truncate_utf8($node->body, 100, TRUE, TRUE)), 
    '%link' => url('node/'.$node->nid, NULL, NULL, TRUE),
    '%thumb' => slideshowpro_get_image_path() . basename($node->images['thumbnail']) );
  return strtr($output, $variables);
}

Now the thumbs and previews work correctly now for me.

I don't have much experience with Drupal modules so someone who does please review and provide a patch.

best,

Marcus