Mostly correct. Nefmoto and Galletto are both flashing utilities. whereas tunerpro is for editing maps and other parameters inside the tune itself. If your ecu is socketed (as some giac tunes were), you might have a problem reading/writing to it (although many people report success). Try reading your bin and posting it in this thread. If you have a successful read, chances are you'll be able to write as well. As far as instrument cluster coding, that will only prevent a soft code (No engine light, missing data from instrument cluster). As for ESP, you will need to recode the ecu for that. Below is the procedure.
http://wiki.ross-tech.com/wiki/index.php/2.7l_T_(AGB/AJK/APB/ARE/AZA/AZB/BEL/BES)#Coding