Ok grabbed some logs last night after flashing back to Stage 0.
Full throttle:
https://datazap.me/u/bimmerag/stage-...&data=2-3-4-13
Boost target and actual boost hold steady around 8psi for the whole pull
50-60% Throttle:
https://datazap.me/u/bimmerag/stage-...13&zoom=22-129
Boost pressure initially spikes to 9 psi on tip-in, but settles to 4-5 psi for the rest of the run
Light Throttle:
https://datazap.me/u/bimmerag/stage-...-13&zoom=0-154
Started at 20% and ramped up to ~40% throttle at higher RPM, but boost pressure stayed around 0-1 psi the whole time
Overall, looks like what you're seeing is pretty normal for a N55. drwillb gave a great explanation that while the wastegate in our cars vacuum actuated, there is a boost solenoid that controls the pressure to the actuator and gives the ECM full wastegate control at all engine speeds and boost pressures
p.s. This was all recorded using the MHD logging function. I have previously used a wireless OBD reader and RaceChrono Pro to log data during autocross/track days and have found that for some reason MHD reads ~1psi higher. For example, at idle with the OBD reader boost pressure read -0.7psi, but with MHD it shows 0.2 psi