Hi there dear queenzoners!, I was looking for a piece of this wonderful demo for ages, and this one was a huge rumour before it saw the day of light recently on the DVD 'The Great Pretender', I thought it never existed (as weel as Play The Game with one of the Bee Gees brother) and this gem was discovered, but I realized that only a few seconds of it were available, take a loot at this link: link
More precisely from 0:58 to 1:05, so I guess this one could be released in full in a near future, what do you think people out there?, cheers everybody!
PTG was done with Andy Gibb, who was not part of the Bee Gees. It was reported on the FC Magazine issue of Spring 1980 (IIRC), which had first hand information from the band.