Thank you Richard, that did help.

I've got pressure working as well.
Temperature is within 0.05°C and pressure is within 1Pa compared to a commercially available BME280 based sensor module.
I thought I had humidity working although it read about 7% off compared to "real" one but today the difference is 30% so there must be something wrong still.

Will look at that later and hopefully be able to post some code.

But geez, these LONG math operatations eats away code space, 8k at the moment.

/Henrik.