I don't know which operating system your using so can't link directly to the correct file, but the selection page can be found here...
https://www.asus.com/uk/Motherboard-Accessories/ROG_Front_Base/HelpDesk_Download/Choose your OS from the drop down list and download the latest driver.
Extract to a folder of your choice and open.
Run the Asus Setup executable to install the Windows driver.
Next open the FBFW folder that is also contained in the same place.
Run the "ROG FRONT BASE" executable.
Click the file browse button "..."
Select the firmware file FB035Exv48.H00" (if installing version 48!)
Click the "Start" button and let it do its thing.
That should be it.
You can check what version of Firmware you are currently running by shutting down the PC, keep power supplied to the motherboard though. Once fully shutdown, press and hold the Front Base select knob for a good 5 seconds. The currently installed firmware version will be displayed in the top righthand corner of the display.