Pathfinder 2e 'Tiny players' struggles?

Looking for help here as I have /no/ idea how to do this or if I even can.

Running a game based around the ‘Redwall’ book series and came across a problem… No matter what I do, the players are 1/4th of a square. Soon as they chose their race (Some for of tiny awakened animal) then they shrink down. So no matter what I do to change the map, they’re always extra tiny.

Is there a way somewhere in either the modules or in forge itself that I can set ‘tiny’ as the default size of tiles instead of ‘medium’ sized creatures?

As an example of what I mean, I have two tiny characters here and a small character. I’d like the tiny to take one token space up entirely and the small to be a ‘large’… But no idea how I could get that to do so

Why not just set them to medium and large respectively?