GvRng, which stands for GvR Next Generation, is a redesign of the original gvr to make it easier to maintain and more stable then the old one.
From a users point of view the biggest change is that GvRng uses GTK as it's GUI and GTK Sourceview as the world and program editor.
The latest version is 1.4.
The drawback is that GvRng is no longer Windows compatible.
Window users can use the old gvr which is based on wxPython.
There are plans to create a Windows frontend for GvRng.