Nice job creating the old-style feel without resorting to the severe pixellation that so many designers seem to think was appealing. It is a bit to simple to be replayable, though.
Adding a story to this type of game is an interesting idea. Unfortunately, the simplistic gameplay doesn't fit the storyline at all. A bit more thought and effort could have made this a great game.
Bug: When engineers stop to deal with caltrops, even far out of cannon range, they somehow still damage the walls. This makes caltrops utterly worthless.
Interesting idea, but a text-only interface is unnecessarily awkward. A mouse-driven interface with text-only descriptions of what you see and experience would be a better compromise.