Hi Refik,
Thanks for noticing and reporting this!
Seems the trim commands were not properly initialized.
The values set in the airframe file were directly written to command_x_trim in fbw, only to be overwritten later from the ap_state->command_x_trim values (which are not explicitly initialzed and hence zero). So when you change the trim commands in settings, only then they are actually applied.
Now the command_x_trim values are initialized in ap_state instead of fbw (and the yaw trim is also set from the airframe file, which was apparently missing before).
Should be fixed in v5.1_devel-148-ga18a74f
Please test and report back.
Thanks, Felix