Created a plugin that deletes MaxiGallery galleries when trash is emptied.

// Remove Galleries Plugin v0.1
// By Dimitri Hiverda
//
// This plugin removes the Galleries made by the MaxiGallery snippet when you empty your trash
// Use the OnEmptyTrash event (Only works from modX 0.9.6 and up)
//


global $modx;
function delete_directory($dirname) {
if (is_dir($dirname))
$dir_handle = opendir($dirname);
if (!$dir_handle)
return false;
while($file = readdir($dir_handle)) {
if ($file != "." && $file != "..") {
if (!is_dir($dirname."/".$file))
unlink($dirname."/".$file);
else
delete_directory($dirname.'/'.$file);
}
}
closedir($dir_handle);
rmdir($dirname);
return true;
}
$deletedids = $modx->event->params['ids'];
$countid = count($deletedids);
$i = 0;
while ($i <= $countid-1):

$table = $modx->getFullTableName("maxigallery");
$rows_affected = $modx->db->delete($table, "gal_id = $deletedids[$i]");

$dir = $modx->config['base_path']."/assets/galleries/".$deletedids[$i];
delete_directory($dir);
$i++;
endwhile;
return;

$table = $modx->getFullTableName("maxigallery");

$deletedids = $modx->event->params['ids'];
$countid = count($deletedids);
$i = 0;

while($i <= $countid-1){
    $doc = $modx->getDocument($deletedids[$i]);
    $templateid = $doc['template'];
    //here switching $templateid and selecting correct table name
    $rows_affected = $modx->db->delete($table, "gal_id = $deletedids[$i]");
    $dir = $modx->config['base_path']."/assets/galleries/".$deletedids[$i];
    delete_directory($dir);
    $i++;
}