HM0360 HW trigger & registers' value retainment

Hello everybody,
I am trying to use the HW trigger feature of the HM0360 sensor, but I have noticed that when I configure the sensor to use theHW trigger (MODE_SELECT=0b1xx) the value of some (most?) registers (such as INTEGRATION_x and ANALOG_GAIN) is lost. The datasheet states clearly that the value of the regs is retained, but it seems that this is not true. For the rest the sensor works as expected.

Is there something I am missing?

Thank you!