Was on 5.0 installed ota Fulmics ROM 5.1-5.2 - Download (MD5: a7afc547b12b6ab3e5566a25bd81054c) via TWRP.
No Problems
Installed Stock Modem/Kernel you linked to.
https://mega.nz/#!fVEi2YYB!FjPwjuhHfbE8gkrXAX4b6ELVaYaa_AybC5DK12fR_zU
Biggest Problem so far.
Mobile Data Connection Not Allowed.
Other Problems.
Airplane mode cannot be toggled off in settings app. Can be turned off in Power menu and pulldown menu.
Rebooting from Power Menu makes the phone hang after shutdown animation; green blue LED cycle. Battery pull and power on behaves as normal after this
Positive: Boot Speed is roughly 34 seconds, or about 1/3 of the previous kernel time (Will actually time it and update (after I make my wife some breakfast))
Going to restore to 5.0 and try again, and update. Then I am removing the modem from the modem/zip and trying that. Let me know if you need logs or other info
EDIT #1 Flashed this Modem
http://xdaforums.com/att-lg-g3/general/modem-d850-flashable-modem-zip-t2936865 (
https://drive.google.com/file/d/0B_m4yeYqRm63c0YwX0JnUGFjQ00/view?usp=sharing )
Before I did anything else. Fixed all known network issues stated above (Airplane and Mobile Data)
EDIT #2 Boot time roughly 34 seconds