s/\\:/x01/g;   # Replaces each "\" followed by ":"
s/\\|/x02/g;   # Replaces each "\" and zero-length string
s/\\~/x03/g;   # Replaces each "\" followed by "~"
s/\\\\/x04/g;  # Replaces each "\" pair
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And there's a zero-length string between each character.

I think you want:

s/\\:/x01/g;   # Replaces each "\" followed by ":"
s/\\\|/x02/g;  # Replaces each "\" followed by "|"
s/\\~/x03/g;   # Replaces each "\" followed by "~"
s/\\\\/x04/g;  # Replaces each "\" pair
[download]

or

s/:/x01/g;   # Replaces each ":"
s/\|/x02/g;  # Replaces each "|"
s/~/x03/g;   # Replaces each "~"
s/\\/x04/g;  # Replaces each "\"
[download]