The phone must boot, did you follow the procedures for installing, did u wipe dalvik/cache(sometimes wiping this will also help, for me it helped while flashing LOS 17.1)Same here. The camera issue is nasty. No other option than to reboot the phone.
@_undead, I tried the latest build. In my case, the phone did not boot up at all. It was stuck on the lineage screen itself. I had to go back to previous build.
Even I am planning to downgrade to LOS17 unless these issues get fixed. If there is anything I can do to help fix this issue, lemme know.