Problem with lcd - pic interface
Now that your LCD works: you see no blinking because you have no delay while the display is blank. So it is blank for 0 ms (which you don't notice), then you display the text for 100 ms (which is what you see). Try

   while(1){
      Lcd_Cmd(_LCD_CLEAR);            
      Delay_ms( 200 ); // added
      Lcd_Out(1,6,"Hello ");           
      Lcd_Out(2,6,"World");
      Delay_ms( 200 );
 }