the overboost is ok for me in this situation , the problem is the fluctuation of boost and wastegate duty cycle after 4500 - 5000 rpm

I don't know why you insist "i igonore you".
It is a mistake . I'm a noob and i try to learn and i make mistakes.
SORRY

Thanks DREAM
I modify and modify and modify my drl and imx. So you and NYET told me the good tuning is without any little overboost at the begining of boost/power/torque?
Kfzw must be modified too because with higher preassure retards appear and must decrease timing ,  this was in my situation , maybe i'm wrong but now with overboost 1.5 bars i have from time to time at higher load only -2.5 only in a 200-300 rpm range.
With cold sparks was the same retard , can i tell worst because i had misfire with bkr7e (with bfr6q don't have).

If You changed turbo to NN, hybrid or something like that, the best solution is first check WG calibration without connected N75 and next, logging pressure at different N75 dutys. One day is needed for me to do this, but after that You have a lot of useful data to create nice IMX table. I done this twice and is better solution than guessing with IMX values.

MŚ.