Worldfiles Puzzle Solved?

At the very least, significant progress has been made on the Worldfiles Puzzle.

QtheC said:

Example of Checkerboard decode
Here is a solution to the tinyurl problem... it leads to an image of a letter that might be another layer to this puzzle, or might be the solution (not sure what all this means)...

Code:
Straddling Checkerboard - key SQUEAMISH

N= 5 O= 1 _= 7 E= 3 _= 2 T= 6 _= 4 A= 0
S=25 M=21 B=27 F=23 K=22 R=26 X=24 =20
Q=45 I=41 C=47 G=43 L=42 V=46 Y=44 ,=40
U=75 H=71 D=77 J=73 P=72 W=76 Z=74 .=70

decipher "ODEWONAK,N" with SQUEAMISH board, but keyword MARYHOPKIN

MA R Y HO P K IN
21026447117222415

O DE WONA K ,N
17737615022405 translate to digits
21026447117222415 MARYHOPKIN keyword
76711256713263 subtract modulo 8
W HO ST HE RE


"Who's There" is the traditional response to "Knock Knock"
the name of the song sung by Mary Hopkin in the "On Our Own" video.


http://www.tinyurl.com/whosthere
redirects to:
http://img408.imageshack.us/img408/9272/plttz0.jpg

The tiny url leads to the following pic