The documentation says use the following for 512KB:
eagle.flash.bin 0x00000
eagle.irom0test.bin 0x40000
blank.bin 0x7E000
esp_init_data_default.bin 0x7C000
master_device_key.bin 0x3E000 (If you want cloud service) ...... not sure if this is required if you don't want cloud service.
I wanted to avoid going through the build effort, but from what I've been reading I'm somewhat concerned that the SDK build is run assuming 1024KB flash.