Looks great and I am a touch jealous. Firstly because it looks the part and secondly because I know you've done it already and if I want one I'd have to do it myself, which due to a shortage of time currently means I'l have to wait a while before considering it.
I've been discussing the Hirst moulds with Revford this week and the pros and cons of using them as opposed to other building materials, (we've been working in foamboard this week for the most part) - The biggest con of course was me suggesting I should make a ziggurat that you could climb up before finding the secret entrance and exploring the interior.