I’ve continued to try to get Wireguard on my MT300N-V2 and the Android app.
After following the GLi-Net instructions I can now connect and browse my home network and connected systems using Wireguard on my 'phone
However I cannot access the internet via the Wireguard VPN (which is my primary aim) - I cannot connect either using website addresses (eg google.com) or a sites ip addrexx (216.58.204.14). I’m assuming that its more than a DNS issue !