That's at least something! Thanks, Marc!
Unfortunately - beyond seeing spheres for totally planar materials - I see no way to actually browse a catalog with Surface Painter.
You have to know what you're looking for and type in a search term. For me, when the search term is blank, rather than seeing all loaded surfaces, I just see some subset (the ones assigned to attributes perhaps - no idea where this set comes from). But, if I type "brick" than lots of surfaces with the phrase "brick" show up. I don't see any easy way of figuring out how to browse any catalog completely - or if I see something, to know what catalog it came from...??
One of the forum moderators
AC 28 USA and earlier • macOS Sequoia 15.2, MacBook Pro M2 Max 12CPU/30GPU cores, 32GB