How to initialize FX Game Data

Love the toolset! Its so easy to use. I have one question, but I’m not sure if this is the right place to ask.
When developing a FX game and using the cart builder, how does the code find where the data has been stored on the flash? I updated a game I was working on, but I have the following code which isn’t correct as it hard codes the data:

#define FX_DATA_PAGE              0x00febe
void setup() {
  FX::begin(FX_DATA_PAGE); // wakeup external flash chip, initialize datapage, detect presence of external flash chip

What should I pass into FX::begin?