OCIO source setup in depth explanation

I’m not a fulltime pipeline developer but I’m trying to improve my python skills in vfx and shotgun/rv. My latest nemesis is setting up an automated RV pipeline with a custom ACES Ocio config.
I already worked myself through the OCIO source setuop sample package and so far everything is working fine. I’m able to load the right ocio.config dependant on the file I’m loading. I can also setup the file transform/look and display so that everything works fine.
What didn’t perfectly work for me was that RV automaticly set’s these groups depending on the file I put in.
I already checked this post:

but I still have problems. I usually end up with a correct load of the OCIO but not a working file transform / display activation.
So I tried the “btl_ocio_source_setup.py” that “mmoshev” posted 2 years ago… (lots of love, helped me a lot already!!) …
With this I managed that RV set’s everything automaticly and in the right way. Unfortunatly if I use this way I’m running into 2 new problems.
First of all I’m not able to disable the file transform or display transform once I’ve loaded a file. It’s not locked or anything but trying to turn it of nothing happends.
The second problem is that it seems that the “output” doesn’t seem to update when I loaded multiple files. I start by opening a “sRGB” jpg and RV works correct by setting the file transform to “output srgb” (so that the file get’s linearized, right?) and the display to “sRGB”. All good so far. If I now load in an exr the file transform is set right but it seems like the viewer is not updating so the exr looks wrong.
Sorry I know this is very basic stuff but I can’t find a very detailed explanation of the source setup and how exactly it works.

I tried out btl_ocio_source_setup.py which was shared by @mmoshev . It seems the display transform is only set once when the first item is loaded by RV. This is why the initial sRGB jpg looks fine but the following exr doesn’t. You can see this in the top level OCIO->Displays. The value doesn’t change per item item in the RV timeline. The original source_setup.py which comes with RV also has the same behavior.
I’m not sure why this route was never taken. Perhaps an RV limitation? Or perhaps it is assumed that review sessions will contain media which all require the same display transform.
My crew desires to see mov files, exr images, jpg images (each which require different display transforms) within the same RV session.

I would guess this is possible, but don’t know RV well enough. After all, each file/sequence is a separate “source”, so you must be able to define transforms per source, no?