Hi,
So that’s how I made it work for me.
I put those lines in Default.txt:
/load addon DrawDistance
/wait 10
/drawdistance setworld 99 (whatever you want)

/wait 10 must absolutely be written before /drawdistance...
Now it should already be applied when the game launches, you don’t need to type the command in game.
The idea is that Ashita must send the command while the game is launched, but as we have to login in the command console first, it takes some time, so we make Ashita wait 10 seconds before applying the /drawdistance setworld.
However, I started playing today and noticed that changing zone might have reseted my drawdistance. So I reapplied it in chat, happened only once in a 3 hours session.
Cheers