I ended up with three errors during/after config:
Compass config failed due to out of memory. Disabling of Sys_Companion solved this.
Level Horizon config fails with error message “attitude estimator not running - check system boo”. I have thoroughly searched for info on this but not found a workable solution.
Preflight check fails with message “no baro sensor 0”. Seems clear it is a faulty sensor but later I have found info which points at this has been solved using other firmware (I am using stable 1.7.3). I have tested other firmware version without positive result but behaviour is such that a firmware problem is remotedly possible. I am new to QGC and PX4 so I have no idea how the the baro 0 can be health checked and logs have not been helpful.
With these two problems the Pixracer is unusable so any help will be highly appreciated.