Wishbone: It's tricky, but as always with ZFR's work, it is also very elegant. I was extremely impressed.
ZFR: For extra elegance, here is a much more compact version
http://pastebin.com/raw/5dsCG0gR This is what I should have created for the challenge. The idea of how to make it smaller without affecting my restrictions came to me just as I was finishing it. But I was in a hurry to post, so I put the larger version that I had, since completing the smaller one would have taken me some time to finish.
I'll let the original stand, but looking at this, and comparing to the original, *might* give those who haven't solved it some ideas (or it might send them in the wrong direction, so be careful).
Well, it's more compact, sure, but I must admit that I liked the elegant simplicity of the original one, even if it is more "wasteful".
Apart from that, I don't think the new version will neither help nor hinder anyone.
Urnoev: If you've seen the message, just do what it says. I searched for a while in the wiki, to see what could fit, and ZFR more or less confirmed it. That's what the edit in the first post is about, by the way. :)
adaliabooks: Yeah, I think I may need to try harder to find an interpreter... I'll have another crack.
Finding an interpreter shouldn't be difficult. Finding one that will actually
work for the full stretch is another matter. If you ask ZFR, he will happily guide you to one that works. Provided you are actually looking for the right kind of interpreter, of course ;-)