I remember the Nickelodeon ride quite well, despite only being 10. I was a massive fan of Nickelodeon as a child, I even went to see the studios in London as a child, and also won a goody bag and all sorts. So when I found out a ride was opening I was very excited!
I remember the outside of the ride being all crazy with pipes and all sorts on the outside, and the main entrance to Cred Street was through the archway near where the driving school is, there was a giant Cred Street sign there.
There was a small cattle pen outside the building (where frog hopper is now) and then a bit of a queue inside. I seem to also remember the staff had themed uniform, I remember white lab coats?
I do remember the computerised alien thing (he was a presenter on Nick). I also have memories of the shadow wall, and the rope bridge area that had a walk way underneath for parents. And also a room where you put your head through various holes to look at pictures, mirrors, etc. And that is one bit where they filmed you for the film.
I have a ride photo somewhere of me and my family, it has all the Nickelodeon characters on it. It's a shame that the ride only lasted for one year, I quite liked it, and its such a shame that the building has remained empty since 1998!
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Edit.
There is a page about the ride here on TowersStreet:
http://www.towersstreet.com/history/past-rides/nickelodeon-outta-control/
And it also contains some photos and plans:
You can also see from the plans, the original ride was going to be called "Nickelodeon: Mind Maze"