Compile ESPController

I’m trying to compile the software for the ESP32 controller for some time now, unfortunately I fail at the “build filesystem image”.
The compile process is not finishing and the file “diybms_controller_filesystemimage_espressif32_esp32-devkitc.bin” is only 512 kb in size.
I am working on a MAC and have tried it on 2 machines with the same result.
Does anyone know advice?