another noob question:
This is how it worked in the 10+ years before the 5120hack?
No corrector for IAT and altitude?
There is LDIATA and KFLDIOPU, but trying to control boost using PWM on a bleed valve in open loop is just asking for disaster.
Worst case, fit a MBC in parallel, and set DC to 100% over a certain requested pressure, and let the MBC handle it.