Thank you aoktar, you are totally right...
After digging around a bit more with regards to "compute model" I might either need a old version of Octane that supports CUDA Compute 1.1 or a newer card.
I think my only solution is to change my MacPro ATI cards while the laptop's Nvidias become ...

just an update on this, the Octane for Cinema4D log window lists:

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OctaneRender version 1.51 (1510000)

CUDA device 0: Failed to find a CUDA binary matching compute model 1.1
CUDA device 1: Failed to find a CUDA binary matching compute model 1.1
Can't Read Preset File: /Applications/MAXON/CINEMA ...

Hi guys, I need a big help on this while I can't figure it out and working on it for a week already.

I have a MacBookPro Mid 2009 with Nvidia GeForce9600M GT and Nvidia GeForce 9400M, latest CUDA drives (6.0.37) and 10.9.2 Mavericks.

I try to use Octane in Cinema4D, everything launches alright ...