I'm using Octane 4, and I'm having the same problem.
Camera focal length animation isn't exporting correctly to .OCS with "octane.saveAnimation"
I'm attaching the Modo scene and the OCS export.
Thanks in advance.
Intel Xeon E5-2680 v3
GPUs 2x GTX1800TI
Windows 10 64bit
OctaneRender 4.00 (4000021) (installed with "OctaneRender for Modo 4.00.0.137" link)
Nvidia driver 417.35