How do I add a new color space (eg, Beta RGB) to the workflow options inside Adobe Camera Raw? I was able to do it inside Photsohop, but not ACR. Is there a special folder inside Windows 10 where I must copy the .icm file into. I already saved a copy of the .icm file inside the C:\Windows\System32\Spool\Drivers\Color folder. But no luck. Does ACR only allow sRGB, aRGB, ProPhoto RGB, and Colormatch RGB?
You see the added ICC profile in Photoshop but NOT ACR? Because that shouldn't be the case nor any different; I see all installed ICC profiles in ACR accessible. No, ACR doesn't only allow those few color spaces you mention.
Author “Color Management for Photographers" & "Photoshop CC Color Management/pluralsight"