In fact there are a whole bunch of "You Tube" videos about this gun, they can all be found here.
http://www.youtube.com/user/construktorALPHAgun/videos
Alex is on facebook if you want to contact him, however he only communicates in Russian and consequently I have been using the on-line translators to do so. I never tried Greek as I know zero about the Greek language (and probably not a lot more in Russian!), but maybe you can communicate in that if you both know it.
https://www.facebook.com/alex.orfanidis.7