To install Taranis OpenTX 2.2 and Add the RF.LUA, follow these steps –
Before Proceeding make a backup of the models and settings Under Read/Write choose Backup Radio to a file.
Go to https://raceflight.com/download and download the required firmware and files listed under the heading “RACEFLIGHT ONE OPENTX LUA SCRIPT”.
Once installed, launch Opentx 2.2.
Click on Settings and Settings again.
Check Mark the option “Use OpenTX firmware nightly builds”.
Click on File and Download.
Click Download FW.
Next, on your Taranis, you will need to enable the bootloader. You do this by pressing the 2 trim buttons at the bottom towards the center holding them while powering on the Taranis. Let go once you see the bootloader.
Then Plug in the USB cable and it should say USB Connected –
Click on Read/Write, Write Firmware to Radio.
Click on Load
Chose the firmware you just downloaded.
Click on Write to TX.
Once Flashed you will have OpenTX 2.2 on your Taranis
You will need to redo your SDCARD on the Taranis. Download the SDCARD Files.
Click here to download – http://downloads.open-tx.org/2.2/nightly/sdcard/
Download the latest file.
Extract the files and drag and drop them onto the SDCARD on the Taranis.
Your Taranis should now be updated.
Go to the the rf.lua file you downloaded.
Open the SDCARD on the Taranis.
Open the Scripts Folder.
Copy the rf.lua file to the telemetry folder.
On the Taranis go to page 13
Select screen 1 change none to script.
Once script is selected go the right and select rf.
Now you have RF.LUA installed. To enable it from the main screen on Taranis press and hold PAGE for a few seconds until the RF Menu appears.
Next discover the sensors.
Go to the Telemetry page: Page 12
Scroll down to “Discover new Sensors”
After it discovers the new sensors. You should see 10 sensors total. You now have telemetry setup.
Here is a great video resource –