I've designed the app so that you can choose your character set - Unicode or ASCII. This is a property of the document and can be changed on the fly, so you should be able to use the tool for text in a legacy environments as well.
It's quite easy for me to support arbitrary character sets, so if there's enough demand, I can definitely implement it. If you can just drop us an email (see "How do I provide feedback" section at the bottom), that'd be great - thanks.
But it won't be supported in the initial public beta build, as we have to prioritise other areas (sorry!).
But it's a cute tool, no question.