I finished running the game last night - it was great fun. Unfortunately I was down 2 players, so their character's chose to stay at Thistle Lodge due to the cold weather. They had just discovered that their landlady's husband was missing although not the importance of this, so they went back to Princetown to notify the police and continue looking into Professor Blackwood's death. They had great fun delving through the library, and I was able to add some more clues here including some extracts from the Ango-Saxon Chronicle and the Domesday book that I appended with suitable fictions for the adventure. They were very pleased with themselves when they realised the significance of the pattern of dates.
They made the correct conclusions at the Dartmoor Prison morgue and decided to return to Postbridge.
When they arrived back, they found that the vicar had called on Mrs Carter (I used the names from the original one sheet) and when they went to search Professor Blackwood's room they discovered the door ajar and the catatonic form of one of the absent player's character (a lock-picking dilettante) sprawled on the floor. After this, they returned to the church (having broken in the previous night but found nothing much due to the darkness) and this time met the vicar, who they were suspicious of, and then they examined the graves more closely. They managed to speak with Bill McArthur and then thought about staking out the vicarage (I had moved the vestry stuff to the vicarage here so that their failure to find anything much in the church the previous night wasn't a plot hole, but they didn't break in to find it). At this point they went on a semi-wild goose chase up to Crockern Tor, believing that this was the place to be, but apart from some acid burned vegetation there was nothing much, so they descended into the woods and staked out the grove. I let the film director character use his massive disguise pool to camouflage them as bushes and they lay in wait for the inevitable denouement.
For a suitably creepy ambience, I played two tracks of Gregorian chanting at the same time and significantly slowed down to represent incomprehensible chants. Then the ritual began. They held their place for almost long enough, but finally broke cover and disrupted it. The Marine Biologist walloped one of the members of the order with a tree-branch then ran off into the woods, the doctor hid in the bushes, the film director took a photograph that blinded the order with the flash and the archaeologist charged into the circle brandishing a prop pistol and trying to grab the dagger
In the end, the Doctor and the Marine Biologist were dissolved by the Wisht Hounds, the archaelogist was convinced to take Carter's place in the ceremony by the vicars force of will and the film director fled in his car, but his photographs when developed all showed carvings and images of the Green Man and the perfunctory police investigation found no evidence of his missing associates. He went back to Hollywood, moved into B-movie horror and died of a heroin addiction in the 40's. So all's well that ends well.
We all really enjoyed the game, and I heartily recommend the adventure.