WPA2 passphrases are supposed to allow all "printable ASCII characters", if CNS limits this more strictly than the equipment itself (nevermind the standard) then there's a potential problem.
If I manually configure equipment with a passphrase that includes '!' (for example) but then CNS won't let me input '!' in a WPA2 passphrase, that's a problem.
I completely agree - this is clearly a CNS bug. If the device allows the characters, CNS must also as well. We'll be fixing this either via a hot fix or a new release of CNS (1.3.1). Timing is TBD though as we're right in the middle of our next release cycle. Can I get an idea of how major this is for you from an operational perspective? This will help me to prioritize resources.