Various ZM thoughts
From ZoneMinder Wiki
Most of these were written when I first discovered ZoneMinder in 2015. ZM 1.28 was the stable release then.
Understanding ZoneMinder's Zoning system for Dummies (Illustrated)
How to use your external camera's motion detection with ZM (and a basic explanation of ZM's trigger architecture)
Modifying ZoneMinder to remember run state names (and why that is very useful)
How to use ZoneMinder with cameras it may not directly support (but you have some way to extract images from it)