My dad had trouble getting the Panzer General / other General Series to run.

iirc, the installer is 16-bit, there's problems with too much disk space and/or too much ram, and then there's cryptic error messages. Oh and the please don't run this on WindowsNT message.

We did find something 3rd party that uses the assets, so all wasn't lost, but ...

Windows has a reputation for amazing back compat, and it's pretty good, but it's not really surprising to find things that don't work. Especially games from that era, there are common issues that come up a lot, but afaik, there's no microsoft compat option to lie about disk space, ram, or vram ... or it doesn't automatically trigger at least.