If you want to effectively remove Score as a victory condition, but keep the Score detail, you can do the following when setting up your game:
1. Go to Advanced Setup
2. Scroll down the right-hand side of the screen to the Advanced Options section
3. Change the "Limit Turns" option to "Custom"
4. Enter an absurdly large number in the "Max turns" box
5. Launch your game
Note that if you set "Limit Turns" to "No Turn Limit" it disables Score victory altogether.