you were on the right path with the letter transformation, but it seems you have made a mistake.

The correct function in Python:

def f(c):
   red = ord(c)
   blue = red + red
   purple = red ^ blue
   green = blue + red
   yellow = blue & green
   brown = ~(yellow & purple)
   cyan = red | blue
   res = cyan & brown
   return chr(res)

You know, it's correct because, if you put in the "Potential Input" (CDFGIPRSI), letter by letter, you will get the gray colored characters (GDNOIPRWU) respectively as output.

This way, in fact R results in R and G results in O.

Now, trying to put the output back into the transformer did not do any good, because it resulted in some non-letter, even non ASCII characters: O D ^ _ I P R \xff U

valid letter transformations in the range A-Z are:
ABCDEFGHIJ -> ABGDENOHIJ
PQRSTU -> PQRWTU

notably, there are letters, that are transformed to itself, being:
A B D E H I J P Q R T U

only a few letters are transformed to different valid letters, being:
C -> G
F -> N
G -> O
S -> W

and for the movie (if it has any relevance) i would throw in Fight Club, as there was a scene where the guys chant "His name was Robert Paulson" or the like... just guessing

Funny discovery though, would love to solve this riddle

PS: the "cane" in the files may resemble to a herding staff...

My guess on the movie is "silence of the lambs" (sheep related), but i guess we dont know until we email him. we are still missing a letter though for his name (assuming the next one is G, still unsure on that)

EDIT: my new guess for the movie is "Black Sheep" because it involves genetically engineering sheep.

nathanle1406 wrote:
"G NOW" does that mean "fist letter is R" and "G now" so.. RG? thats a complete guess.. i cant think of any names spelled with RG.

G now, huh? Hrm, is that were the solution, then are all the symbols just a distraction?

M
A/V
N
Y
O/N

So we're all clueless... that's it, Clueless! High school comedy! What does that mean? High school comedies are all about boning and proms! Proms are like a... date... The Shepherds collective is secretely a website to date sheep!

http://www.youtube.com/watch?v=BgdV1IVkk8E

Great Scott -> favourite catchphrase of Emmett Brown in back to the Future
decked -> maybe relating to Rick Deckard, protagonist of Blade Runner
batty -> Roy Batty, another figure, as Amalfitano mentioned

now at least we have some names...

EDIT: also "replicate" is mentioned... -> Replicants
EDIT2: Blade Runner was released 1982... "between Alien and 1984", like mentioned in the letter
EDIT3: Great Scott may also be a reference to Ridley Scott (director of Blade Runner)!! so all spaced written words relate to Blade Runner
EDIT4: Los Angeles also seems to be spaced written... it's the scene of Blade Runner... gues the case is clear here

Adrian Shephard (with an a instead of an e) is the main character in the HalfLife expansion "Opposing Force" and also appears in Portal in two ways:
- Aperture Science Handheld Portal Device - ASHPD - Adrian Shephard, though this was coincidence as stated by the developers- a keyboard with all letters of Adrian Shephard highlighted can be found in the game: A D E H I N P R S
from the letters, only N cannot be validly transformed by the circuit (guess it has no meaning though)

The Reply for asking, if his name was Roy (Batty):

My name isn't Roy, but here's some feedback:
Don't give up, you're on the right track!

Quote:
If confirmation is your aim,
give both the film and my name

(is he reading these forums? or is the fact he said "confirmation" and i said "confirm" just a coincidence? my email just asked if the motion picture was blade runner... actually never mind, of course he is reading this)

If you notice the end of the letter is worded a bit strangely. The first letter is the only one that matters? I take this to mean the first letter of the film's name. "B?"

I think his name may in fact be "Rob," he just wants us to get it without guessing.

The circuit must solve for "O" because that's the letter the shepherd's cane translates to.

ETA: I messaged him and got this returned.

Quote:
Let them know: It has truly begun.

https://dl.dropbox.com/u/94591457/8152019.html

It's a countdown. Looking into the spacing and capitalization of the message. I tried Baconian and binary to no avail.