Have been testing out the save to defaults orbx feature quite a lot and it seems to be working great. The only bug I have found so far is when making a change to an already saved to default orbx material, and re-saving to default. A error occurs and the original orbx file seems to loose its embedded textures, as the file size reduces to about 15KB.
Other than that so far it is working great
I have been talking to Otoy about using the ORBX format for storing "Default" materials - and there are some complexities with this strategy which are of concern. For example, if you have a default ORBX material containing a texturemap, if you copy the rvt file to another PC - you will need to also copy the default ORBX files (since the texturemaps used in the .rvt reference texturemaps inside the ORBX files). I think this is going to be confusing to users - particularly where you have saved a "Default" which contains a texturemap from the Revit materials library - which would exist on other PC's with Revit installed. Plus, once you have saved a default for a material, there is no way to edit and resave that ORBX (for technical reasons that I won't bore you with). The above issues exist with the LocalDb too on Octane Standalone (ie. once you have saved a material to the LocalDb, you cannot update it and re-save to the same LocalDb name).
So I think the best solution is to change the "default" material save format from ORBX to OCS. With OCS files the texturemaps are on your filesystem, so you can manage where they are stored and ensure they are copied onto other PC's when the .rvt is copied. Plus the OCS format is "future-proof" for any changes make to the Octane node structure and when loaded Octane will automatically convert the nodes form the Octane version they were saved in to the current Octane version of the plugin.
Happy to explain/discuss if people have questions...
Paul