So...by mistake I formatted my usb stick/flash drive where I had all my .max files of my scene (I save incrementaly, as recommended by 3D Buzz). So, it seems that I will have to find my will, someday, to restart this project...
Computer Type: Desktop
Operating System: Microsoft Windows 7 Ultimate (64-bit)
Processor: Intel Core i7 (2nd generation) 3.07 GHz
Graphics Card: NVIDIA GeForce GTX 470