If it's importing all tracks to the melody you can just show the channels separately and delete the midi on that channel by selecting all notes and delete.
EDIT: I just tried it on your xml, uncheck Import All To Melody then select each channel and delete the notes, melody was on ch9 on that xml.

You can chroma key the background color out of the big lyric window, I think Reaper has a chroma key, once you key out the background you put an image or video in the track below and it will show thru leaving the chords and lyrics that are another color.
EDIT: there's also an option to have chords in the lyrics.

Last edited by Pipeline; 02/17/19 03:44 PM.
Biab Track Injector for Reaper
Free Biab Chord Picker Tool