Looking at qrencode website (https://fukuchi.org/works/qrencode/), there are windows port such as http://code.google.com/p/qrencode-win32/, but it's a bit outdated. Besides, there are lots of QR code software/library on Windows, surely there are few which support more than 1K character.
There might be but it seems like everything is gone online now. They want to let you do everything "online" through their website. I guess they hoping someone puts in their private key.
