[Lenovo Zuk Z2 Pro ROMs, Kernels, Recoveries, & Oth] Terminator.J:
Chiming in after a day of using it...

Setup: just did a full QFIL 1.9/3.1.194 - OTA 3.5.388 bring up just a week or so before to last AEX 5.8, with official TWRP 3.2.3 (fun fact: with platform-tools r28 you no longer have to do the -i flag on fastboot commands. it won't even accept it if you try) that includes all of cosmedd's latest github changes and baseband from 3.5.388. Wiped data, cache, dalvik, system, and vendor (mount vendor then rm -rf /vendor/* from shell in TWRP to clear it), tidied up the contents of /sdcard to just have my photos, music, ringtones, and installer files (deleted android & data dirs).

Trying to find a gapps to use, my wife has a Pixel XL and [MENTION=614507]razorloves[/MENTION] is the LineageOS maintainer there who just brought up unofficial LOS 16.0 build for sailfish/marlin, and he has a slightly tweaked MindTheGapps 9 ARM64 package that seems to actually work and get through the setup wizard on his AndroidFileHost: https://androidfilehost.com/?fid=1322778262903983907

The data transfer chunk kept failing so I had to set up as new (bummer, that saves some time, but oh well), but it actually leaves you with working Play Store, which didn't work when I tried the official MTG for Pie package from javelinanddart's page here: http://downloads.codefi.re/jdcteam/javelinanddart (look in 'misc' instead of 'gapps').

Okay, so I'm booted into Pie! With GApps installed and other phones complaining that I just signed in from a new device and need to review my account security settings! Sweet!

Quick poking around the Magisk forum reveals that there's a guy distributing bleeding edge builds from github (thank you [MENTION=7187684]ianmacd[/MENTION]) and it worked great so I didn't try 16.0 or 16.7beta. So I've got rooted Pie and my Google account set up so now I can restore useful stuff with TiBackup, woo. This is promising.

Notes:

- VoLTE seems to be back at circa 5.3 levels of "well maybe it'll register with IMS services after 2-3 attempts to place an outbound call and having it eventually fail over to 2G after trying to dial out for 30+ seconds", which is a shame because it worked GREAT every call in 5.7, and then was at "maybe every other call" in 5.8. And there's no status bar indicator right now, so it's just try and hope that it connects with the HD symbol on the call screen.

- After reboot it complains that you changed your SIM configuration and need to pick one for data/messaging, even if you didn't move it and only have one inserted.

- Can confirm dark theme only applies to a few things and not actual apps like settings or dialer or contacts. Substratum requires an act of congress but I guess that's just Android 9.0 and at least it works if you 1) have a compatible theme, then 2) go grab the last 998 beta from their Telegram channel, 3) only choose "build and update", 4) reboot, 5) THEN select all the built overlays & enable, and 6) reboot again just to be on the safe side. Because this is the price we pay to have OLED friendly dark/black themes because Google knows best and wants to be like the fruit company and blind everyone with power-hungry white-getting-whiter default appearances.

- Phone encryption worked. AND, wait for it, TWRP 3.2.3 can decrypt it, too! Caveat: use a 4-digit PIN in standard layout, because when you boot to TWRP, it'll have a 3x3 pattern grid instead of number pad, but if you swipe the pattern that corresponds to where the numbers WOULD be (so PIN 1234 corresponds to upper left, upper middle, upper right, middle left) then it'll unlock & decrypt data okay. Whew! Well the police are siding with white supremacists so if you're gonna take your phone to a rally to try and run Nazis out of your town you might need a little protection for your data.

- Yeah, auto brightness isn't working.

- FC of settings app when trying to open Accessibility page.

- No navigation pill? I guess we need to edit the build.prop to add "qemu.hw.mainkeys=0" again like before SmartBar and stuff got added to the Extensions template, but I haven't tried it because I've already got screen burn-in from nav bar buttons and figured I'd just get used to swiping the fingerprint sensor.

- Can't edit the built-in APN settings if it includes a "dun" server type, and can't manually create my own APN setting that includes it - I get a warning about the carrier disabling the ability to do it. If I wanted carriers to be able to control my handset and put artificial restrictions on network capabilities that I'm already paying for, I wouldn't be using a custom ROM. This is unacceptable and needs to get reverted. The built-in APN settings for my carrier are slightly incorrect, and I can't fix them without losing tethering ability.

- Boy something is amazingly better about Bluetooth; the Pokemon Go+ BT wristband was failing to connect all over the place in Oreo, but that was kinda the same for everyone no matter what device. But it registers in-game right away now, every time. Cool!

- Overnight drain was less than 1%, although it still seems to drain fast when screen is on. I'll post some SOT numbers in another day or three once the new battery app-binning heuristics have a chance to settle in.

I do miss having SmartBar just to have arrow left/right cursor control when typing (along with expanded desktop so I could just swipe them up when desired and not have nav buttons keep burning in my screen), and there were some fiddly things with software setup but I'm sure we'll get the full extensions template & proper GApps sooner or later.