Sorry, which version of Mac Os are you using exactly, and which GPUs do you have in your Mac?

For Mac CUDA versions you need a Mac equipped with Nvidia GPUs, Mac Os High Sierra 10.13.6, CUDA 418.163 driver, and latest Nvidia GPU driver for 10.13.6.

ciao Beppe

My sistem: macOS 10.13.6 (17G14033 ...

Help!!!

Please help! What can I do to make it work?

Please make a version for High Sierra (CUDA)

It is already available.
Here are the latest links:
https://render.otoy.com/downloads/0f/b2/e5/8c/OctaneRenderPrime_for_OctaneServer_MacOS_2020.2-23.1-xb.zip
https://render.otoy.com/downloads/87/9d/eb/99/OctaneRender_for_OctaneBlender_MacOS_2020.2-23.1 ...

Please make a version for High Sierra (CUDA)