#define X_HOME_DIR -1

#define ENDSTOP_X_BACK_ON_HOME 25

#define NUM_EXTRUDER 2

#define VIRTUAL_EXTRUDER \

Could you tell me the signification of :   #define MOVE_Z_WHEN_HOMED  ?

I have a compiler error with 1.0.4dev (Arduino 1.8.9 - Board Mega 2560) with    "#define EEPROM_MODE 1"

#define DISTORTION_CORRECTION_R 80 works fine !!!!

#define DISTORTION_CORRECTION 1

#define Z_PROBE_Z_OFFSET 0

#define DISTORTION_EXTRAPOLATE_CORNERS 1

#define DISTORTION_CORRECTION 1

#define Z_PROBE_X1 -69.28 #define Z_PROBE_Y1 -40 #define Z_PROBE_X2 69.28 #define Z_PROBE_Y2 -40 #define Z_PROBE_X3 0 #define Z_PROBE_Y3 80

#define ZHOME_X_POS 999999

#define ZHOME_X_POS 999999

#define MAX_FEEDRATE_Z 4

#define ZHOME_MIN_TEMPERATURE 0

what about #define HEATED_BED_PREHEAT_TEMP 55.. should I set that to zero? Thanks again.. Richard 

#define HAVE_HEATED_BED 1

You must delete also the #defines which override old value that you want to keep. As programmer it was clear for me, but I know I did not say that.

#define SDSS            10