If the directory containing the jcurses.jar and libjcurses.dll files has a non-URL character anywhere within its absolute path, the load will fail. This is especially problematic as a space is translated to %20 and so the loadLibrary call fails.
The solution is the load the directory name as a file: URI and convert that to a file string rather than using a URI as a path directly. I have included a patch that I created as I needed it to work immediately. I have only tested the problem and fix on Windows XP.