The quicklook feature appears to be broken. Typing "ens", highlighting a note, holding shift, then pressing enter causes the following error to be written to the debug console:
[22:50:09.357] ERROR: Evernote[Run Script] 152:154: execution error: The variable ql is not defined. (-2753)
EDIT: upon further investigation the error appears to be coming from the "⇧" path of the "ens" script filter, which is a run script action with the osascript:
which is clearly a typo. I tried making the obvious changes (e.g. putting "-ql" inside the quotes) but I couldn't even find anything in "en_open.scpt" that looks like it'd do quicklook, though I'm not super familiar with applescript so I could be missing something.