The edition you can get from Steam runs mostly alright, with a few caveats:
- You need to rename medieval2.exe to Launcher.exe (see Tips & Tricks) to make it launch from Steam.
- Fonts are messed up in the settings dialog and a few other places (menus, etc) - generally the tooltips tell you what the button is, or you can guess from context.
- The loading screens don't display once the progress bar starts moving.
- Windowed mode doesn't work (gives 'Unspecified error' when you launch with the option '-w' or set windowed = 1 in medieval2.preference.cfg)