Hi typophiles!
Largely motived by the excellent feedback I got on the previous thread in which I posted the first "code escape" of the Cornu-based curve editor, I am now releasing a second version, as a source tarball for Unix-like systems.
I believe that the segfaults reported by Robin Houston are now fixed (the ones due to coincident points due to his patch, the other ones due to numerical instabilities when spirals are too close to perfect circles).
But the main thing you'll notice are the usability improvements; just click on a curve to insert a knot, or press Ctrl-D to delete one. You can also select (and move) groups of points at once. Double-clicking a curve closes it, and Ctrl-click makes a corner point, so you don't have to do the click,Ctrl-T combo.
As before, you need either Linux (or anu reasonable Unix) system or OSX with Fink set up for development. The main libraries are Gtk 1.2 and Libart-2. I will post a native OSX version soon as well.
Feedback is always welcome. It's possible at this point that I am going to pursue making it into a real product and/or licensable technology, so don't be surprised if there's a period of quiet followed by some kind of announcement.
) Also the 'corner mode' is redundant; Ctrl-click in curve mode is wonderful and sufficient. Two global modes, together with a clear visual indication of which you're in (like a different mouse pointer) would be fine I think. 
