someone posted a good example of using the C(++) bsec library on github, (filled in the gaps in the bosch example and some explanation on how to compile) I can confirm using the pizero precompiled bsec library works ok on an old raspberry B as well.
I posted an issue explaining how using latest bsec library download and fix the high pressure reading using the other, later, bosch library on github. (though ironically the bsec library is later release date it still has the high barometric pressure reading problem, which I tested compared to assorted bmp/bme sensors)