I'm using Houdini 18.5.532 with Redshift 3.0.39 and I've been trying to check the Redshift render settings on some older Entagma tutorials, believe most were made in Houdini 17-17.5, so not that old, but if I don't have Redshift open I always get this warning with broken material nodes showing up in the mat context:

houdini bad node type found: redshift_vopnet in /mat

skipping unrecognized parameters...
...and, pretty much all RS parameters are skipped...

However, if I close down the project, switch to a Redshift layout and then open the project again, less parameters are skipped and the materials show up in the mat context, but I still get skipped parameter warnings for the materials like the ones in the attached screenshot.

At this point, the materials seem to render correctly, but I wonder if the skipped parameters are something I need to be concerned about? I imagine this is because the Redshift material nodes have changed slightly over the different Houdini and/or Redshift versions and parameter names have changed. Am I correct in thinking this?

That said, do I always need to have a Redshift layout up, when opening a project where RS was used? If I have Redshift installed it would be nice if Houdini just automatically recognized all the RS parameters. Would that be considered a bug? If so, should I report it here or on the RS forums? If not, do you have any tips for opening RS projects without breaking everything?

Nah, it's the way Houdini works.

I've even seen warnings after saving a new project and opening it back up using the same version. WTF? How come Houdini can't understand the file it just wrote..?

Not sure if it is related or not but this is what happens when you start with new scene in 19.0.501 (it is even worse in 19.0.455), put down component builder, save it and open again: