Honestly I never thought of it, would have been cool to add something like that. I could maybe update it, what would you have in mind? Sweetwillow is on the kings road so they definitely must have been some skirmish at least.
Honestly I wish I had thought of this while originally making the town, gives it a really cool feel, especially as it was previously burnt down in a dance.Some evidence of raids in the surrounding areas, whether that be burnt fields, forests, villages, or just a light plundering. There could be evidence of the townspeople camping out in the castle bailey, hiding from the Lannisters. I should imagine Tywin left the castle alone at any rate as they wouldn't be equipped to lay siege to it. Strategically, Tywin thought he was meeting Robb head on somewhere along the Green Fork, and would have been marching north quickly to try and get the jump on him. It's likely most of the sacking happened on the way back to the Crossroads. Tywin at this point hasn't learned of Jaime's capture so he might not be as inclined to just burn everything he sees, but I think there's a strong case to be made that he laid waste to the surroundings on his return march.
I don't think Sweetwillow would have got off lightly... the Kingsroad goes right through the town.