Sorry, but Just so I don't keep forgetting, the installer for Linux puts the libs and dat files in the wrong directory for Linux Mint. It's no biggie but it does get tedious after a while. In Linux Mint the liboctane.so and the octane.dat files need to be put in /lib. Currently they are placed in /usr/lib. I'm testing out the new version right now, thanks.

Jason
PS: One more plug for an appimage version of the plugin, it will fix these kind of issues. Two would work, one for the server, one for the modified Blender.