
Rookies (1927) and Detectives (1928) have been screened at Cinecon.
London After Midnight (1927) is famously lost. The Big City is lost, although a trailer with only artwork, no scenes from the film, survives.
Trent's Last Case (1929) does survive, although it is missing a reel.

Under the Black Eagle survives too, but I'm not aware of any festival screenings.
