Given the repeated "tt" and "rm" patterns, one common guess is Atbash (A↔Z, B↔Y, etc.) or a Caesar shift.
Given it’s from a paper (or puzzle), the intended solution might be for the whole string except "Download-" . Download- nwdz lshrmwtt khlyjyt fatht layf ttshrmt...
Instead, maybe it’s (common in puzzles). Given the repeated "tt" and "rm" patterns, one
The phrase "Download- nwdz lshrmwtt khlyjyt fatht layf ttshrmt..." appears to include an English word "Download" at the start, followed by what might be the result of a cipher applied to an instruction or filename. one common guess is Atbash (A↔Z
Given the symmetry in ttshrmt , maybe it’s a simple substitution with key derived from "Download" .
Right shift: n→m, w→e, d→f, z→/ → mef/ — maybe part of a path.