Be careful with how you use playback limits with interactive music. Playback limits are specified anywhere in the hierarchy, but end up being applied to "sounds". In interactive music, the equivalent of a "sound" is an audio clip (that is, a region of an audio source laid out in a segment using the Segment Editor).
Thus, if you set a playlist container's playback limit to "1", there will never be more than one audio clip playing. Now, imagine that this playlist loops a segment over itself, which has one track and has a pre-entry or post-exit region, and the transition rule says "play pre-entry and post-exit". At the end of the segment, the pre-entry of the next scheduled segment will start playing. At that time, you actually have 2 audio clips that are trying to play! Since the limit is 1, one of them (the "newest" or the "oldest") will be stopped instantly. This is definitely not what you are trying to achieve.
Worse, the same problem arises if this segment doesn't have a pre-entry or a post-exit region, but its track is streamed with 1 second of "look-ahead time" (defined in the track's properties): 1 second before the end of the current segment, the audio clip of the next segment is instantiated. Since that brings up the total playing instances to 2, one of them will be stopped.
