There is a basic, but free version, available of Tacview (https://www.tacview.net/features/comparison/en/
You can also try out the free trial for the full version for 21 days and like most stores there are sales (end of last june price was 50% off).
Tacview is most usefull in combat flight sims like Digital Combat Simulator to review the action (or view in real time in the advanced edition).
For beginners (like me) this shows you who shot you down.
A small example might explain more (tacview combat review around minute 5) : https://www.youtube.com/watch?v=aFF3hnvkcOI
I fear that with larger scenarios in CMANO 2 things might get crowded on screen.