This extension is simple and does its job.
Even though it ins't still marked for Joomla! 2.5, I used it with J 2.5.3 and VirtueMart 2.0.2.
It works well!
I used only the single image function by now. In the future I'll try it with videos.
Two little matters:
1. when the image popped up image is larger than the screen, the rounded right corners (for example Light Rounded Theme) hare cut
2. in the popup window the alt="alternate description" of the thumbnail is visible. I think it shouldn't.
Anyway, a very good job.
To speed up my work, I created a text template containing the text code to insert in the articles (in HTML mode), so I have just to set the correct parameters.
Thanks for your effort.