Please, please please please please!!! submit this as a bug to the c4d team. I and many others have experienced this issue. I'm 99% certain it has nothing to do with Octane, and everything to do with Maxon's implementation of xrefs.

I've been trying, on and off for a couple of weeks, to render a black shadow pass. It seems like there's a discrepancy between the OSX and Windows versions of the plugins regarding which options need to be enabled.

No - that's the main problem (at least as of 3.06.01) - the Octane dialogue doesn't save anything on Windows unless the C4D save options are also used. It renders the images to picture viewer, but the files are not saved to disk.

It strikes me as odd that in order to save my files I have to uncheck the save option. For me the expected behaviour would be that no files are saved.

So - with that in mind, I have checked the save option and rendered to tiff.

IT WORKS!!!!!

Definitely different behaviour between OSX and ...

sure:

I think I found the culprit.
Octane Render settings are not recognizing those tokens you're using, so it's not outputting them properly.
The layers you're getting are from the C4D multi layer dialogue

Try this (in the same file you posted, so its exactly the same comparison):
[*] Uncheck the main ...

yep, here's the simplified scene:

I think there must be something wrong with either my project, my installation of C4D, or me. I still cannot get the black shadow pass out.

So far I've tried:

Saving only using Octane's save dialogue - result: no saved images, at all. They're saved to the picture viewer, but not my drive.
Saving ...

Token support (at least for me, on this version) has gone backwards. In 3.06 I was able to at least save out the passes from the octane dialogue to the right location, even if the folder name for the passes was not correct.

So far, just this:

http://i.imgur.com/VG4rbzr.png

It worked on the previous version, but the tokens were saved out as "$pass/$take" rather than "foo/camera_left".

With this version, no files or directories from the Octane pass system are saved. The target directory only contains the native ...