Thanks for your time.
I went here (the only working env_particles_custom tutorial I found) and attempted the tutorial, (which began with "load up worldcraft"). I think I shuffled things around to work in Steam more or less, but the order of operations the tutorial seemed to be saying is:
Build a map, stick an env_particles_custom entity in the map, give it a name and particle sprite, start with the particles flagged for "on", run ns in developer mode, use editps to bring up an ingame editor to work with your particles.
That's as far as I got because typing editps <name> doesn't do anything noticeable in my client.
I saw a lot of people ranting about n00bs asking questions about particles, so if this is an easy fix that I just missed, sorry for the extra post, but I don't see the answer.
Thanks again for your attention.