At last I found final solution to use ACES in all lighting conditions in Octane. It produce perfect equalized gamma and vivid colors as should be. Without dark, shadow clipping areas. And all of that saved using native ACEScg file.
The problem : ACES was developed for real cameras which works in real lighting conditions where outside light intensity produced by direct sunlight or scattered light in atmosphere is hard to achieve without exposure system which works only for point of view or averaging whole view.
This is why images or film stored be real cameras works fine with ACES. In computer generated images where we works with artificial light conditions especially architectural visualizations ACES produce very dark and even clipped ( RGB 0,0,0 ) areas.
I think that CGI generated skies like Hosek&Wilkie or HDRI maps are not compatible with ACES system.
Solution :
To compensate darkness there is need to crank up sky power to values near 8 but it produce problems with materials.
I found that for ACES default Hosek&Wilkie values are wrong. Strenght of Sunlight should be much lower than power of Sky. This will produce much less dark shadows and overall brightness would be better. But this is not final solution.
The best is to crank up camera exposure by 600-800% and lower overall Sun and Sky values by 70-80%. This will produce perfect equalized gamma with great highlight compensation without any badly darkness but still with the most darknened areas at RGB 0,0,0 where they should be.
For example. When I use for my most strong sunlight exteriors Sky power at 4 and Sun power at 1.25 I must crank up camera exposure to 6-8 and lower Sky power to 1 and Sun power to 0.5-75 to make ACES looks perfect. Without changing any material parameters.