Hey chief rowmanns,
Please check if the upload went through, I've used the Corona website one. Zip file is called WaterSim-InternalError.
I have cannibalized the scene heavily, but the problem can be replicated. Go to frame 300 (animation is between 300 to 400). Start the IR, leave it for a couple of seconds to render then stop it. Go to frame 305 or something, start IR, leave it a bit, stop the IR. On the 3rd of 4th time it should crash.
I hope it's a workaround to this because I'm getting desperate here:))
EDIT:
I am running Windows 10 build 19041.450 - Ryzen 3950 X, 64 GB, GeForce 1060 GTX 6 GB. The scene is on an NVME SSD (plenty of free space). VRAM consumption is around 4 to 5 GB.
Thanks!