Golf 4 1.9 TDI AXR, Stage 1

[piragnaqwest]

Hello friends. I have a golf 4 1.9 TDI AXR from 2004 with 420000km+ and I would like to give it a stage 1 but I am new to this (beginner/noob) and I don't want to do stupid things and maybe mess up the ECU (happened to my other car) so I would like some help from you (a specialist). Original file is attached.

Maybe you can give me some tips in the future to be able to do tuning


Thank you so much, you rock!!