https://www.youtube.com/watch?v=VyB5cvA6f78
EDIT: I see he posted a link at the bottom of the Readme.md I guess I should have scrolled to the bottom first.
I run DPII in DoxBox on Linux like this:
dosbox DP.EXE
Something I don't see in your app is the Perspective tool.
This is surprising given it's a web application in modern age, did not expect that.