Frankly I don't know, but anything made the last 10 years should the trick.
Anything that runs Python/TK and has a GUI, including, but not limited to, Microsoft Windows, Linux, Mac, and UNIX.
Probably because you haven't installed Python. If you still have problems, send me an email at anders AT knatten DOT org.
The next version is released when finished. An indication of progress is given at the Future Plans-page. If you want a feature, tell me! Send an email to anders AT knatten DOT org and ask. Even better, if you are a good programmer, take a look at the Developers page. Maybe you can help out?
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