We have a diverse fleet of the MAX Transits deployed all managed through InControl2 now running with Firmware Version 8.
If you are managing this through InControl2 you can rollback the firmware from there to FW7.1.2 using the firmware management menu options at the device level.
Alternatively, if you are using the devices web interface to manage the firmware, then you can under the System tab select the Reboot menu option and reboot back to the previous firmware.
Once you are back on the previous firmware, you can reattempt the firmware upgrade again, download a fresh copy of the firmware from the Peplink website if you are doing this via the devices local web interface.
If you are still having issues, then we suggest that you contact your local Authorised Peplink Partner for specialised assistance.
If your local Certified Peplink Partner can not help you with getting your router going again, then you can raise a support ticket through the Peplink Contact Us, look for the Open a Support Ticket » link.
Happy to Help,