Did you guys manage to discuss this yet?
I am having a problems converting old scenes, using Itoo library assets to ACES.
As an example, your material "_RC_Slate_Roof", applied to the "Railclone Library/Architecture/Exterior/Roofing/Tiles/Slate 1", uses 8bit grayscale maps in the diffuse slot and 24bit RGB maps in the glossiness slot.
I'm not sure why the texture was created like that, but it leads to the wrong transform being used for both the diffuse and glossiness, when using "Auto", so something to bear in mind.
See the Chaos Docs for more info: https://docs.chaos.com/display/VMAX/VRayBitmap#VRayBitmap-ColorSpace
Could you consider adding name tags to your bitmaps filenames? eg:
-for 8-bit color maps(diffuse/translucency/textured lights) include "_sRGB" in the filename.
-for HDRIs or linear exr files used for diffuse/translucency/textured lights include "_Lin_sRGB" in the filename.
-for maps used for bump/normal/displacement/roughness include "_RAW" in the filename.
This is an extract from a post by Muhammed_Hamed of Chaos: https://forums.chaos.com/forum/v-ray-for-3ds-max-forums/v-ray-for-3ds-max-general/1112300-what-does-default-do-on-a-vraybitmap-s-rgb-color-space-dropdown?p=1126456#post1126456
I really hope you can add support for ACES soon!