Multiviews

Several sources on one picture, for monitoring. Same job as an ATEM Multiview or a TriCaster multiview.
There is no cap on how many you can store in the session. How many monitor windows you can open at once is the video output destination window limit in Settings.

Layout and tiles

Templates are Preview+Program plus a grid, or 2×2 / 3×3 / 4×4 and similar.
A tile can be an Input, a Scene, or Mixing Unit Preview/Program.

Add and refresh interval

Add one under Settings, or from Multiview at the bottom right of the main UI.
Preview refresh can be thinned. Lower it on a weaker PC so monitoring does not hurt performance.

Each open Multiview window uses 1 slot for real-time Preview/Program/Multiview display. Closing it frees the slot. Closing the main window closes Multiviews and exits the process.