Tack said:

I once heard from someone who said that they had a 16mm print of ESB that contained some audio idiosyncrasies. Namely, Luke lets out a little scream as the floor gives out under him in the Cloud City vents. Is this on Puggo Strikes Back?

The 16mm print used for Puggo Strikes Back does indeed contain a completely unique mix for the film that differs from both the mixes heard on American 70mm prints and 35mm prints, but no little scream from Luke in the Cloud City vents is heard in this mix.

I believe that someone you heard from might have been thinking of the cheesy scream in the Vivaldi teaser trailer: http://www.youtube.com/watch?v=EH9z8se3Aho

Thankfully that scream of Hamill was never heard in any theatrical release. But, we got something worse in '97. ;)