Found this link on the Ligotti forums of a clip of a short silent film version of Lovecraft's 'Silver Key.' To be honest, it really doesn't do much for me, but I thought I'd post it here in case it it might be of interest to someone.
http://www.youtube.com/watch?v=lF1sXfDYamM
There was also this link to an old BBC Lovecraft radio documentary that might be of greater interest, although the host site containing the MP3 is down for maintenance at the moment, so I can't vouch for its content I'm afraid. But I'm sure it'll be what it says it is...
[www.mediafire.com]