Just watched it today - was a bit of an odd programme, didn't seem like it knew what it wanted to be, was certainly not "Inside Alton Towers" in any great way, lots of guff nothing to do with Alton and the dreadful enthusiast sections (not that I'm saying those people were dreadful by any means, just thats not an "Inside Alton Towers" thing - if they wanted to make a human-interest story about enthusiasts then that was the place for those stories, but as it was they were far too light-weight as a human-interest story and didn't add to the Alton angle at all). Some parts of the Wicker Man sections were good, but again it lacked the narrative to tell the whole "building the Wicker Man" story (as it ignored so much that we know about).
Pretty wasted effort all round then, poor film-making overall IMHO.