The Drupal BMLT component has just undergone a radical rewrite. All three of the CMS plugins now share a common code base, so they present exactly the same administrative interface as each other.
First, fetch either the Drupal 6 module, or the Drupal 7 module from their home on GitHub (Click on “Downloads,” then, in the wndow that comes up, select “Download .tar.gz” or “Download .zip.” This will bring a TAR GZIP, or a ZIP file onto your computer, decompress this file, and rename the resulting directory to “bmlt.” Then, view this video for installation and activation instructions. Once you have the module installed, go to the BMLT settings, and read this page for guidance on administering the plugin.
Once the module is set up, then read this page to get guidance on how to make the BMLT instances appear in your articles.
You may also want to look at these pages for ideas and examples. They demonstrate WordPress plugins, but the process is almost exactly the same for Joomla! and Drupal.