In this scheme it indicates the ports and numbers that correspond to each pin. For D4 it would be PG5 and the timer that controls that PWM output is the T0B. As I indicated in the previous post you must change these values.
It should look like this:
//Control Digital Pin 6 which is Servo 2 signal pin on Ramps 1.4 board
#define SPINDLE_TCCRA_REGISTER TCCR5A
#define SPINDLE_TCCRB_REGISTER TCCR5B
#define SPINDLE_OCR_REGISTER OCR0B ///////////////
#define SPINDLE_COMB_BIT COM0B1 ////////////////
// 1/8 Prescaler, 16-bit Fast PWM mode
#define SPINDLE_TCCRA_INIT_MASK ((1<<WGM40) | (1<<WGM41))
#define SPINDLE_TCCRB_INIT_MASK ((1<<WGM42) | (1<<WGM43) | (1<<CS41))
#define SPINDLE_OCRA_REGISTER OCR5C // 16-bit Fast PWM mode requires top reset value stored here.
#define SPINDLE_OCRA_TOP_VALUE 0x0400 // PWM counter reset value. Should be the same as PWM_MAX_VALUE in hex.
// Define spindle output pins.
#define SPINDLE_PWM_DDR DDRG ////////////
#define SPINDLE_PWM_PORT PORTG ////////////
#define SPINDLE_PWM_BIT 5 // MEGA2560 Digital Pin 4
It should work.