Was this ever fixed? I think I've seen this happen. It's like there are some set positions for enemy waves to appear from. Even if you expand onto that area and kill the nearby base the spawn location remains.
Maybe the algorithm for spawning could be changed to something like this:
- let p be <the point the spawn would normally start from>
- let v be the vector p - <position of the player's crash site>
- let v' be the normalised vector v
- while a player building exists within 32 tiles of p...
- let p = p + v' * 32
So in other words, the game would move the spawn point directly away from the player's starting location in a straight line by 32 squares at a time until there's nothing around.
This should preserve the general direction of the attack and it won't push the attack much farther out than it needs to.
(Actually this touches upon an important question about this mod: what is the ultimate goal? If it's about long term survival and repairing the space ship isn't enough, then the player will need to keep expanding. Survival consumes resources since there are infinite enemies and the walls have to be repaired all the time and new ammunition built.
So if the goal is to make a kind of mega factory of survival, it's important that expanding works in a way that makes sense and is fun. Enemies appearing inside of your walls doesn't make that much sense. :) )