- Load up the latest Open Rails build.
- Select a route, activity, etc. for demoing the bug and start it.
- Get the game in to a position where the bug is demonstrated or easily triggerable.
- Save (F2) and quit.
- Go in to Visual Studio, and open the RunActivity project properties (Right-click "RunActivity" in Solution Explorer and select "Properties").
- In "Debug", under "Start Options" enter "/resume" in to "Command line arguments".
- Run the project (F5).
- Check that the bug is fixed.
Steps 5 and 6 only need to be performed once for each copy of the code you have, since VS remembers the setting.
You can repeatedly run the project with F5 after each tweak and see how things look; unless you make a new save, you'll keep resuming from the same place each time.