Hi,
The config file should now be located in the aircraft's main directory, next to the acf files. It is called g5.cfg. It is the same format, just with many additional items, as the old acfConfig.cfg file, so if you are migrating from a V1 aircraft to V2, you can rename and move acfConfig.cfg to g5.cfg. This file is automatically generated on aircraft load if it isn't there already (just quit the same and make the modifications necessary).