<>
With Nyquist in Audacity it’s sufficient to give te sound object as a return-value back to Audacity, see Nyquist and Audacity → Return Values
As edgar said, you don’t usually need to use (cue …), but in the code that we were discussing recently involving (at …), (cue … ) was necessary because (at …) acts on behaviours, which are different to sounds.
There is a section in the manual about sounds vs behaviours http://www.audacity-forum.de/download/edgar/nyquist/nyquist-doc/manual/part3.html#23