Gif might be possible (as in switching images) videos are currently not supported.

Let's try a gif first?  

I'm creating a mod and I'm modifying the game's pregame. I'm trying to replace the images with a video I created but so far without success. I would like to know if it's possible to make this change and if anyone can help me.

yeah and the templates exist in the base game, just aren't implemented yet.  We've played around with that too on historical. 

Frankly, for my simple SP gameplay, capturing is quite a convenient and fun strategy as it enables getting a foothold in enemy territory and also get resources  (=new troops) from nearby.

In DelendaEst there is the additional concept of slaves (with a limited lifetime due to the hard life they are forced to endure). Could that be the additional working unit you are looking for?

Do chariots really have to be that fat? Feels like many QoM (Quality of Misery) measures over time, en masse since RC2. Some trees or houses and my heroine isn't where she's supposed to half the time; here she's stuck on a citizen. It's agonizing to frequently watch my champions take the scenic route around a mountain or something...