I'm the developer of a program called newton, which combines some elements of FVD and AHG in a graphical, user friendly environment. For the past several months, newton has been in beta testing on coastersims, but now that it's reached the 1.0 milestone, I now feel comfortable releasing it to a larger audience.
Basically, newton allows you to create elements based upon forces and roll values (just like FVD, though there is not a 100% overlap in functionality) without the need to post-processing the track in AHG. It is also extremely fast--you see the changes you make in real-time. Here's a video of an earlier build in action:
And here's a screenshot of the same (early) build running in Vista:
In summary, the first version of newton will offer the following relative to FVD:
<advantages>
+ graphical GUI in a single window,
+ the ability to specify non-zero laterals,
+ heartlining built right in...no need for AHG,
+ upstream changes automatically propagate downstream,
+ it's easy to see which section you are currently editing,
+ optional gimbal-lock free quaternion pathway,
+ it's faster by, like, a lot;
<disadvantages>
- can't specify separate times for banking and forces,
- will not be able to create transition formulas.
If you wish to download it, you'll need to know a few things before you do:
XP users: You'll need to download and install the .Net 3.0 Framework (~50 MB) from Microsoft before newton will run.
Vista users: You're ready to go out of the box.
To install newton, just download the zip file and unzip it to a directory of your choice. If you decide that newton is not for you, simply delete the folder (XP users can then uninstall .Net 3.0 if no other programs on their machine depend upon it).
newton comes with a readme file that details the change log and warranty information (regarding the warranty, basically there is none)--be sure you read that before running the program. There's also a pdf file that briefly runs through the basics of the interface (though most of it is pretty self-explanatory by just using it, IMO).
That's pretty much it. Enjoy!
Download link: newton 1.0.0.
Edit: fixed broken link; added YouTube video.