What hides between Shadow and Light?

[Kedjane]

Pretty sour that there was an error in the sequence all along.
I suck at codebreaking, mainly because I mainly visit this forum at night. I can still think logically though, so can anyone find a relation between the words "snare", "sloth" and "smear"?
They have all got five letters, begin with an s (he might have chosen all s words because it's an easy letter to begin the code with or because it has to be an s) and unless the first words must be solved first if some relation is found between snare, sloth and smear that could help us with the rest of the words.

Anyhow, that Vernam thing leads you to a cipher. Can anyone make anything out of that wiki page? I'm not natively english so I'm not familiar with several words plus I'm not good with codes in general and the Vernam cipher seems hard (how can one solve a code with a random key if the key is not known or every single possibility is not tried?).