Seems to work ok. Some console deprecated warnings are coming but does not prevent software from running (yet). Great work!
I never really understood IMU data section.
- structure len = 36
- first 4 bytes = timestamp (in tens of microseconds, divide by 100'000 to get seconds)
- not sure if after that is following data (typical or potentional data of IMU devices, also checked from IMU chip datasheet)
* accelerometer raw values: ax, ay, az
* gyroscope raw values: rx, ry,rz
* magnetometer raw values: mx, my, mz
* euler: alfa, beta, gamma
* quaternions: x,y,z,w
But for GPX file output IMU-data details does not really matter.