Thanks for your bug report. The help file section describing /var -n is not very well worded :-]
The purpose of the -n switch is to prevent /set and /var from treating the value as a calculation. In other words, /set -n %var 5 + 2.
The /set -p switch does the same thing but also preserves "text" quotes, including empty "" quotes.
There are several ways to prevent a variable from being evaluated, eg. $evalvar(%var,0) or % $+ var, and so on.