OCIO Color Space Transform not saving selected colorspace in 25.3.2

I can confirm that I'm seeing this issue as well using ACES 1.3 Studio in AE 25.2.2 Win 10. I'm going from ACEScg to ARRI LogC4 and the plug in is working as expected (Visually going from ACEScg to ARRI LogC4 in the comp window) but it's showing ACES2065-1 in both Input and Output Color space. It looks like it switches when the project was closed and reopened, possibly after an application restart. 

Hi Sébastien,

I've just made a test project in 2024 (24.6.7) with a single adjustment layer with an OCIO transform set to ACEScg to RGB. When opened in the Beta (25.6.0) the effect did revert back to ACES2065-1, so the 2024 to 2025 is confirmed on my system.

The other projects I'd been seeing it happen intermittently in were projects that had been saved recently in 2025, and I don't think any of them originated in 2024 either.

Okay, I had to go back to 25.1, since this also seems to be linked to the Clipping issue reported in a different thread: If a blending mode is present, sometimes it clips the footage, which seems OCIO is defaulting a transform to sRGB instead of ACES.

I can confirm that I'm seeing this behaviour as well.

When loading saved projects, the OCIO colour space transform effect intermittently loses the saved options and reverts to default values in the dropdowns for input and output ('color_space_picking: Output - sRGB').It appears to just be the labels in the dropdown that are returning to the default values, the effect _seems_ to hold the underlying transforms that were previously selected but the labels are wrong and show the default value.

As it's intermittent, will keep an eye and send a file if I can reliably reproduce.

Win 11 24H2
AE Beta v25.4.0 (Build 82)

NVIDIA Studio 572.16

I've noticed that overall, the OCIO Color Space Transform effect is not behaving as expected and it is breaking from time to time in certain projects, so I suspect it has to do with the version of OCIO and ACES AE is using. I've switched to a custom OCIO profile and so far it seems to work as expected.

(This is Windows 11 Pro 24H2)

It happened on every project done prior to this version. I'll pick a project to give you, due to NDAs and stuff. If I open an old project, strip it and save it, now the change is permanent and color spaces are lost. I'll send you a DM.