I would prefer a slightly different mechanic for the worm:
- it appears next to the player's buildings - in free area, and does not ram them out of the ground
- if the ground is covered with concrete (or reinforced concrete - solved through the settings) - the worm cannot dig out
- the worm cannot dig out in water (or deep water - solved through the settings), but can always dig out in shallow water
- a digging worm will spawn other units (similar to the behavior of a worm in StarCraft)

or Can we fork this mod (if you don't want to implement this)?

My problem with worms is the standard turret AI they use - you can't force the worm to target non-military structures, so ramming from underground is the main destructive force right now. Once they are out, unless there's bots in the air or turrets/radars nearby, worm will just sit there and do nothing until player shows up to fix the intrusion.

Worms can't dig out on water - that's already implemented. Worm will dig under lakes, but can't go to the surface. It will TRY to dig out on the shore if there are targets there, but will die after few tries if collision box overlaps water tiles.

As for the fork - sure, go ahead. This is not my mod in the first place, I just updated it after it's original creator left it.

You can create a special invisible turret entity with a small hitbox over all plain buildings - all worms have splash damage, so they will try to fire your turrets, and start damage to all players buildings.

You can create those turrets only for a target worm zone and in some radius. If worm dies - remove turrets. All turrets without ammo or with infinite ammo and zero damage