Well, the easiest way to release it is to program a release list that has the release as a comment macro. To play each of these, the Guard button needs to be disabled just above the cuelist window.
You could also program a similar single cuelist where the first cue is whatever you want to have. The second cue is a blank cue with the release as the cuelist (ie in the comment macro RL1 for releasing cue list 1). Then in the options, use "reset on release" as the option and pressing it the second time will release it.