I tried to install this exporter in modo 501 sp3 only to find that the menu doesnt show up.
After some forum searches over at luxology it looks like lux changed the way menus are added. I fixed fs_OctaneExporter_GUI.CFG so the menu now shows up.
Get the 1.05 script here: viewtopic.php?f=34&t=2985'
then overwrite C:\Users\USERNAME\AppData\Roaming\Luxology\Configs\fs_OctaneExporter_GUI.CFG with the new one I've attached.
This only fixes the menu... I have no idea if everything else works in 501