Not only I can do it. Anyone can.

Open that demo and play it. Then reconstruct it your way with software, red curser lines, and the tracks view of your favorite DAW. You will experience the difference between understanding audio generation and Post-generation editing. BIAB is not a DAW and while it is a marvelous tool for generating tracks for manipulation in a DAW, it's better at creating tracks internally that are as complex and of equal quality in minutes that takes hours to duplicate in a DAW. The demo proves it. More proof is 100% of songs, lessons, and demos by PG staff is finished as a BIAB SGU file. No cakewalk, Reaper, Logic, Pro-tools , EZ Drummer, or other EZstuff to be found. The DAW'sers are doing it backwards.

In BIAB, no need for a fully modular GUI, or need for users to create their own "panels". No need for better sorted or better worded menus. Learn how to use the program as it's designed rather than try to mold it into a post editing software program. It did not take me years to learn BIAB inside out because I learned it's purpose, it's design and I used Multi Track recording principles rather than back into DAW editing of exported tracks.

<< OP title reads: "My only wish is to make Band in a Box easier to use." >>

I don't think if the OP or you open that demo and then try to replicate it by backing into it manually generating multiple instrument tracks, comping them, manually arranging them in the tracks view of your DAW into that same arrangement, neither of you will come and post how much faster and easier EZ Keys or Reaper can make that same stereo final mix.

You, the OP or anyone else, regardless of experience with BIAB, can use that single demo as a template to create their own song, in their preferred, key, tempo and chord progression today all without years of struggling with menus, windows, cursers and such.

BIAB 2025:RB 2025, Latest builds: Dell Optiplex 7040 Desktop; Windows-10-64 bit, Intel Core i7-6700 3.4GHz CPU and 16 GB Ram Memory.