If you want, I can help you write a for a forum or social media that references this mysterious ciphertext — something like: Title: The cipher behind the download
It might decode to something like: “this text is from some source” — because “lbnwth” (6 letters) could be “source” or “mystery”.
Given the context (“Download” in subject), maybe the ciphertext is a phrase like ?
Given the complexity, this may be a or part of an ARG.
If you have the actual decoded text, drop it below. Otherwise, try brute-force ROT from 1–25 — one will yield an English sentence.
But I realize: If I shift : n (14) -5 = 9 → i w (23) -5 = 18 → r d (4) -5 = -1+26=25 → y z (26) -5 = 21 → u So “nwdz” → “iryu” (not English).