Flashing steps for Pong
hiroshi.***If using orangefox, skip the steps below and simply flash the ROM zip***
Download recovery, vendor_boot, dtbo and boot images for Pong from here.
Reboot to bootloader.
fastboot flash recovery recovery.img
fastboot flash vendor_boot vendor_boot.img
fastboot flash dtbo dtbo.img
fastboot flash boot boot.img
Reboot to recovery.
While in recovery, navigate to Factory Reset → Format Data/Factory Reset and confirm to format the device. (for clean flash only)
When done formatting, go back to the main menu and then navigate to Apply Update → Apply from ADB.
adb sideload rom.zip (replace "rom.zip" with the actual build filename).
(Optional) Reboot to recovery (fully) to sideload any add-ons.
Reboot to system and enjoy!!!