Hi, thanks everybody for the tips and suggestions. In the end, I mostly googled around, took what I liked from here and there, and ended up with something good enough for the time being (later on I will tweak it again, mainly for the greying-out of images, which I didn't do it right now, but should be easy replicating frames).
In case it can be useful to someone else, I put the example here: http://angel-de-vicente.blogspot.com.es/2013/04/presentations-with-org-mode-beamer.html (in Linux to view the embedded video you need Acroread 9.4.1 or later (or so I think). In Windows or Mac, I have no idea if the embedded video will work. Cheers, -- Ángel de Vicente http://angel-de-vicente.blogspot.com/
