Here's a video using BBPlugin as a Live Arranger.
The song has 228 bars of 14 chords in C, 8 bars each so it will loop the 8 bars unless another chord is enter with the midi keyboard.
You can have 2 or 3 BBPlugins to give more chords and endings.

Watch https://www.dropbox.com/s/jgybno1v1xg9j2r/C-Chords-Reaper-BBPlugin-Arranger.mp4?dl=0

Download C-Chords-Reaper-BBPlugin-Arranger.mp4