This is an amazingly huge project! It's very well done.
I ran into some things I couldn't do:
I tried to change the background and it gave me a pen to paint with but didn't actually do anything with what I drew. What I really wanted to do was use the background from my computer, i.e., copy a file into the project.
Similarly, I wanted a way to save documents I wrote in your editor and to save pictures that I painted. What this really means is that I want a filesystem inside the program. Maybe that could be done with browser store?
In the paint program I wanted to use tools other than the pen (rectangle, circle, all those things).
In the browser, I could do a google search (there should be a duckduckgo option, or more generally, a home page choice) but when I clicked on a result, nothing happened. (I want it to load the page!)
In the calculator, I wanted to use the result of one computation as input to another computation, e.g., (2+3)*4.
I see the problem, The drawing was for a different option in "Custom Features Settings."
I must have accidently saved the wrong version, It has been fixed now!