OK - so working with Justin in the BDLL Telegram Group - we have this workaround to get to the live desktop
get to a tty screen, login as live and then `sudo eopkg install nvidia-glx-driver-current'
once that has completed type `sudo systemctl restart gdm'
this will take you to the desktop where you can then install as normal.
You may very well have to drop to a tty again after install - upgrade and then do as above to install the Graphics drivers.
This I have not tested as following install Solus faills to show in the UEFI boot menu. but that is a WHOLE other story.