[Advanced Help Request] Lineage 18.1 GSI + TWRP + Magisk + Gapps

I would like to request a step by step guide to install Lineage 18.1 GSI + TWRP + Magisk + Gapps please! (This exclamation indicates begging, not demanding)

Expected/Requested format:

  1. Use SP Flash Tool & Teracube_2e_06_20201116 to get to a stock setup
  2. Download file A
  3. Download file B
  4. Command 1
  5. Command 2
  6. Command 3
  7. Etc.
Background: (click to expand)

I currently work as an “I.T. Assistant” and consider myself to have a wide marsh of I.T. related knowledge with the deepest part being dinking around with Android. That being said I just cannot seem to get this setup to work. I have primarily been trying to merge these 2 guides as base guides:

https://community.myteracube.com/t/how-to-install-lineageos-17-1-gsi-on-the-teracube-2e/2691/3

https://community.myteracube.com/t/advanced-users-only-twrp-recovery-root-for-teracube-2e/1729/20

I have probably spent 20-40 hours trying to figure out how to get this to work and I finally “gave up” and am asking for help. I have had tons of ideas along the lines of “maybe if I try this!” Toward the end I noticed my new google searches were resulting in pages of purple (clicked) links. My new ideas were failing to bring me new information.

I am not going to flood this post with everything I’ve tried because the post would be far too large…and honestly I can’t remember half of the things I tried and I didn’t document my attempts. That being said I will link the file names I’ve been working the most with.

Files used/tried: (click to expand)
  • lineage-18.1-20210914-UNOFFICIAL-treble_arm64_bvS.img
  • lineage-18.1-20210914-UNOFFICIAL-treble_arm64_avS.img (not sure why bvs is the file that has to be used since we’re not AB…this file resulted in boot loops)
  • MindTheGapps-11.0.0-arm64-20210920_084011.zip
  • open_gapps-arm64-11.0-nano-20211007.zip
  • vbmeta.img
  • twrp-3.5.2_10-2-Teracube-2e.img
  • twrp-3.5.0_10-2-Teracube-2e.img
  • Magisk-v23.0.zip
  • Windows 10_MTK+VCOM+USB+Preloader+Drivers.zip
  • MediaTek_Preloader_USB_VCOM_Drivers_Setup_Signed.zip
  • MTK_Android_USB_Driver.zip
  • platform-tools_r31.0.3-windows (verified adb and fastboot are 31.0.3 via adb --help and fastboot --help)
  • SP_Flash_Tool_exe_Windows_v5.2048.00.000
  • Teracube_2e_06_20201116

I believe the main issue I am having is either a TWRP issue or zip file issues. I am not sure if TWRP is responsible for “knowing” how to work with our dynamic non-AB partitions or if the zip files are supposed to have the information to handle that? I don’t think I’ve been able to install anything through TWRP without some type of error. I also noticed when TWRP is installed I cannot get to fastbootd and TWRP fastboot mode does not work at all. The command “fastboot devices” lists nothing from within TWRP fastboot mode. If I click switch to TWRP adb mode and try “adb devices” I do have a device show up.

I’m at a loss for what to do but will be very responsive in testing any guides anyone posts and quoting the exact error I am given at various points.

Thanks in advanced to any random internet hero who takes pity on my soul and helps!