I got this working on LibreElec/Kodi, using the following guide https://seo-michael.co.uk/vpn-manager-for-openvpn-openelec-kodi/ This uses the Zomboided VPN Manager add-on available here https://github.com/Zomboided/service.vpn.manager I only needed to specify my AirVPN login credentials. I needed the generated OPVN file from AirVPN, but only needed it later during the installation, when prompted. I didn't use the installation wizard. Hope this helps others with the same problem.