Have you tried gog.com? They support the games they sell, and often patch them so they can work on newer versions of windows (or if old enough, provide a custom dosbox launcher).

They do sell Sid Meier's Railroads ($9.99), and if you check the support forum it may be obvious if they've fixed this problem.

Having to buy it twice isn't optimal, but you get bug fixes and a DRM free installer you can download and keep and manuals in PDF form which beats trying to keep old floppies or CDs in good condition. I've bought quite a few old games I had from them for just that reason.