Just my twopennyworth regarding a hold chord ending.
I use this type of ending often.
What I do is this - if your song ends at say Bar 70 with a held chord, type it in as X.... (it goes red after input)and then extend your number of bars in song to, say, 75 or so. Regen the song. It should play the hold at bar 70 and onwards until it crashes into the BB induced ending around bar 74. It will play that ending too and I simply snip that off in DAW.
If you only want, say,a single instrument or selection of your chosen instruments to play from bar 70, use F5 to mute the unrequired ones.
I almost always use RTs but I can't think why it wouldn't work with midi tracks as well.
Bests
Ian

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