On the docs page
docs.limesurvey.org/Assessments
the link to the Assessment example (Limesurvey_sample_survey__Assessment.lss) downloads an empty file. :unsure:
And click on the link to the file, there opens an other page, which allows you to download the file:
I downloaded the file this way before, and I did it again. If this doesn't work for you (I don't know why it shouldn't though), I'll upload it here in the forum.
Help us to help you!
Provide your LS version and where it is installed (own server, uni/employer, SaaS hosting, etc.).
Always provide a LSS file (not LSQ or LSG).
Note: I answer at this forum in my spare time, I'm not a LimeSurvey GmbH employee.