Hi Leena,
The two FIRMWARE_VERSION values show what version of the code you are using. You will see it on the serial monitor when you first start the OLA.
The OLA_IDENTIFIER tells the code what version of the code was running when the settings were written to SD card or into EEPROM memory. If the code knows the FIRMWARE_VERSION is v2.0 but it sees that OLA_IDENTIFIER is 0x117 (v1.7), then it knows the settings on SD card or in EEPROM memory are invalid, and so it will use the default values.
If you are using the OpenLog Artemis firmware, you will only see the Quaternion data from the DMP if you enable it. Use Menu option 3 to configure the IMU, then use option 12 to enable the DMP.
Best wishes,
Paul