can you post the firmware source code ?
does it auto zero out the pf and mohms for the measuring wires ?
Honestly i never measure or check the mohms just check it with inductance and Capacitance further i do not have source code only Hex files as author of the project did not release it.
hxxp://inx.narod.ru/lcfm/lcfm1.html This Russian guy convert the code or rewrite it for 16 segment LCD display but he did not share any code or even Hex file only schematic.
hxxp://www.electronicslab.com/projects/test/024/index.html This guy made it with firmware version 1.35 (my uploaded is 1.25 which is more stable)
hxxp://scopionz.blogspot.com/2015/11/simple-and-accurate-lc-meter-circuit.html This guy made it own PCB and share it experience
Not least but last i found the link to original author web page from my record which you can see in links below on page 7 you can find the all firmware version but only Hex files, author of the project discuss the theory of operation in detail on first three pages.
hxxps://www.hobbielektronika.hu/cikkek/lcm3_alkatresz_mero_muszer_-_kit_lehetoseg.html