You should be able to start the client itself by executing its binary from the installation path, by default you can find it at ~/.local/share/Ryzom/ryzom_live/ryzom_client
Can you download the latest Ryzom Installer version from download.ryzom.com, extract ryzom_installer_qt file and run it? It should work even if you just extract it to your ~/Desktop folder
Can you run the Ryzom Installer from a terminal and see if there are any useful messages written there while you are using the installer?
Maybe one of files is broken, can you backup your ~/.local/share/Ryzom folder (for example by renaming to ~/.local/share/Ryzom.orig) and try a fresh instalation? (this will requires additional ~8GB of free space in your home directory)
Can you download the latest Ryzom Installer version from download.ryzom.com, extract ryzom_installer_qt file and run it? It should work even if you just extract it to your ~/Desktop folder
Can you run the Ryzom Installer from a terminal and see if there are any useful messages written there while you are using the installer?
Maybe one of files is broken, can you backup your ~/.local/share/Ryzom folder (for example by renaming to ~/.local/share/Ryzom.orig) and try a fresh instalation? (this will requires additional ~8GB of free space in your home directory)