Spoiler thoughts from me:
Some non-spoiler bits, found out during the Press Night:
-Kieron Smith, Global Artistic Director for The Dungeons, was described as the "writer and director" of Ghost Train. What they means exactly I'm not sure, but in any case, it means that this has had significant input from someone who is in charge The Dungeons, which are very successful, and what this attraction should aim to be like.
-The park acknowledge this will take some time to perfect. As with things like this, there will be a need to be responsive to guest and actor feedback, and things like timings, scripts, etc may need to be tweaked. The park will do this.
-Not having the restriction of an IP means it is easier to change / update the story too.
-A general consensus from everyone I spoke to who rode it was that it was perhaps the best they could have done given the constraints they had. There's a "ride system" in place, but it is minimal and restrictive, and was designed for a very specific purpose. The building was designed for that ride system. Replacing the ride system is pipe dream worthy at this stage. But what they've with it, and what they've turned Ghost Train into, is (as I've already said), on the higher end of what they could have done. They could have done more, but they've done a good job.