I run into the issue that when I turn on collision separation, the pressure field disappears and the particles disintegrate. I can't say if it's actually due to the pressure, but it's the only field under visualizations that disappears.
I have tried it with collisions using both a static object and a volume source, and the issue occurs with both methods. The collision object itself remains available and can also be divided with the option.
Unfortunately, I have not found anything in the documentation under Collision Separation that could describe this subject.
In the figure on the right, "Collision Separation" is on.
Sure there is. Use the Get menu at the top of this page to click Download. Scroll to the bottom and click Production Builds. You can install an old version side-by-side with the new.
Using Houdini Indie 20.0 Windows 11 64GB Ryzen 16 core. nVidia 3050RTX 8BG RAM.