Great sound and atmosphere akin to the original!
The streaming version is a bit slow to load and didn't load at all just now (download was quick though, thanks!), maybe add a mirror?
Some suggestions that might be interesting to look at:
- Perhaps lower the emphasis / focus of the bass pads at the start of the sequence, let them ease in a bit more, as they dominate the build up too much IMHO. Consequently also when reaching the end sequence.
- To break repetition, maybe look into putting a part in between at a higher tempo, with a bit more beat, creating a more "impending threat" atmosphere. Then ease off again to the original pace.