Well the chord track itself doesn’t really have any specific octave info associated with it - a G chord is a G chord independent of the octave it is in. However when you have the chord track play back via an Instrument or MIDI track then the chord will be played using the voicing settings you set in the inspector of the Chord Track. So for example if you have it set to use piano voicing it will play notes for the left and right hands that fit nicely on the bass and treble staffs. When you analyze an existing midi part to generate a Chord Track the octave info is lost and not included in the chord track.
Personally I’d never use the Chord Track to play an actual part, since it is fairly limited in what it can do (i.e. block chords played one time whenever a chord event occurs). Mostly I use it to sketch out a progression and tryout various alternative progressions (such as different chord substitutions). Then once I like the progression I’ll mute the chord track and drag the chords down onto a midi track to create a midi part with those chords (or just hand enter them in with the Key Editor). After that I edit the new midi part to have it play the chords the way I want - changing the voicing, arpeggiating the chord etc. The Chord Track isn’t really designed to play music, rather it assists in composing and documentation.