Ok lets do this!
First open /data/English/Only-SP/Techs_Amarian.xml from the TechDef "Civics" find and Cut out this block.
Code: xml
- <GameModifier>
- <ModType>Player</ModType>
- <Attribute>UnlockCityAction</Attribute>
- <StrVal>RushProduction</StrVal>
- <Icon>Consumption_Icon.png</Icon>
- <Provides>Can Rush Production</Provides>
- </GameModifier>
then go to /data/English/Core Improvements/CoreImprovements.xml
find the <ImprovementType InternalName="CityHub1"> block.
Scroll down to where the <GameModifier> blocks begin and add the block from above.
Now when you plant your first city Rush Production will unlock for you.
PS. There may be a better place to put this than the city block but this functions correctly as far as I can tell (Note I just did it right now and instantly rushed a merchant on turn 1 so if you find any bugs with my method please let me know!)
PPS. I realize editing CoreImprovements is unwise compared to using the mod folder. But this demonstrated the concept quickly and efficiently and as far as I know you have to change the TechDef in the Core files anyway so it seemed better to just add the block back into the Core.