Hi,
I discovered this old game and its fantastic.
too bad the graphics and interface are so outdated (dont tell me about nvidia-only bridgeit please :)
i think you guys should consider again releasing a new version with improved graphics, and added levels, that also let you construct buildings (not just bridges) with varying wind etc, and maybe earthquakes and so on.
You could even make the levels a real small campaign with a little background story, and make randomly the ground shake (earthquake) in some maps.
i do think such a game as a big potential
otherwise, i'd suggest releasing the engine as open source and let other people realize that. (the engine seems long and difficult to get right, otherwise i guess i'd have started my own "copy" of it already)
Good luck anyways
ps: your website and forum also would use a lifting :P
There is a new version of Bridge Construction Set in the work which will address many of your ideas. The web site is also in the process of an overhaul :)