I was playing the Steam version of A:D today, and just briefly I noticed a "radar" (a la Defense Grid) along the bottom, showing icons for the next enemy units due to arrive. It only happened once, and I couldn't figure out why, or how to make it happen again.
I thought maybe it was because the entrance was off-screen, but various attempts to reproduce the effect failed.
Am I missing something? While the radar isn't necessarily essential to gameplay, I'd be interested to know why it magically appeared just once.
Awesome game, by the way. Awesome series too. Big fan, although A:WE will always be my favourite.