Never mind my stupidity. Just found the answer in the forum.
viewtopic.php?f=44&t=63471&p=341071&hil ... ze#p341071

The viewport will only render the size of the current window size. It look as if final render will actually render in the correct size, but it will always make save button gray (unelectable) and I cannot save the end result.
Final Render is not explained in the manual. Actually the manual really ...

OK, figured it out.
Any scene saved with the demo version cannot be reloaded and rendered any-more.
The licensed plugin can save and reload.

@Paul: I strongly suggest to document this in the download page of the demo version, as it is not documented and this is a very big limitation.
Current ...

hm, unfortunately that was not it. I bought the license and it behaves exactly the same. I cannot render a scene that was saved and reloaded.
Now I really need help.

My apologies - I misunderstood the issue you were having. The DEMO does not save any Octane data to the .duf file. This issue only occurs in the DEMO version, and the subscription and regular versions do not have this issue. I will add a pop-up message when you save in the DEMO version to make this ...

Thanks Paul, but I believe that OctaneRender_for_DazStudio_3_8_0_38_Win64_DEMO is the last version?
Anything that i can try to do?
Any log files to submit?

I updated Daz Studio to latest version 3.10 and can still reproduce this major problem.
Can somebody confirm that he CANNOT reproduce this with the release version?
I'm hesitating to buy the actual plugin, as it might show similar behavior in on my system.

I'm thinking of buying this plugin and I'm using the latest demo version (OctaneRender_for_DazStudio_3_8_0_38_Win64_DEMO) to test it with Daz studio 4.9 64bit.
I found a strange behaviours that I cannot believe is normal, as nobody would be able to work with this plugin, so need help to figure out ...

Bug ID 3
Reproducability Always
Subject Some Carrara transparent shaders will render black in Octane.
Description Take a primitive object (Sphere) and add the Carrara basic shader Crystal to it. It will render black in Octane.
Workaround Add an alpha value of 0 to the carrara shader.

Bug ID: 2
Reproducability: Always
Subject: Changing other (not "Rendering Camara") camera settings will trigger rebuild.
Description: Moving or rotating a camery other than the "Rendering Camara" will trigger a rebuild of the octane plugin sceen.
Workaround: Wait.