At last, after two weeks and a new programmer, a 16F767 working blinking code:

@ DEVICE PIC16F767, INTRC_OSC_NOCLKOUT ; System Clock Options
@ DEVICE PIC16F767, WDT_ON ; Watchdog Timer
@ DEVICE PIC16F767, PWRT_ON ; Power-On Timer
@ DEVICE PIC16F767, MCLR_OFF ; Master Clear Options (Internal)
@ DEVICE pic16F767, PROTECT_OFF ; Code Protect Off

OSCCON=%01110000

main:
High PORTB.7
Pause 500

Low PORTB.7
Pause 500

GoTo main
End