Hiya Dwayne,
I wasn't aware of improvements to the physics so let me know what they are and maybe Dick will take them on or some other adventurous fellow. We had Marv Keur to do them along with Dick last time but Marv is busy taking flying lessons so I don't think he'll be available to do it this time.
For someone wanting to do this, this is how you should proceed. First, the 'official' rollingstock packages need to be installed and the changes applied. Since this upgrade would be optional the file changes put in their proper folders need to be sent to me in a zip so I can unzip these files in a mockup folder structure similar to MSTS. The changes should be at least somewhat beta tested before being sent to me. I'll create the installer and then I'll put the file out for further testing. Once the consensus is pleased with the results then we would make the upgrade an official part of the install.
May fortune favor the foolish.
Rich Garber