Willard Hi!
Yes, the file you linked is correct.
Normally, all characters over E000 won’t be displayed in any other font except Bescii, because those Unicode points are what’s called “Private User Area” or PUA. That’s a part of Unicode reserved for any person to define the character as they please, and what anyone can do there is different, so if you copy, say, E000, it may show something in Bescii and something completely different is Atascii (another of my fonts) simply because different characters are defined.
In most fonts, though, you’ll see squares, or blank spaces. This is normal, as most commercial or general use fonts don’t define anything specific in these Unicode spaces.
So, you can open the demo file in a browser in Windows XP, and as long as you are using an app that supports Unicode, that square you are copying should show the correct character when displayed using Bescii in BASIC Engine.
Working like this is a bit going blind, but it’ll still work in the end.
The way I set up the demo folder will normally display the characters using Bescii in any modern browser, as those support web fonts, but I think browsers in Windows XP had poor support for web fonts, or don’t support modern web fonts at all, so you’ll have to resort to copying the squares and hope you’re getting the correct character, I’m afraid.
As for knowing which character is what, I can provide an image with the characters and their position if you need it as a reference, so let me know and I’ll put it here for you.
Putting these characters in the PUA is the correct way to handle them, but sadly it makes it a bit impractical to use them in older systems. Make sure you're using Unicode everywhere, as any re-encoding may ruin the result.
Whatever you need, let me know. Cheers!