My sister raised this question, and it's been on my mind ever since. I've played a bit with the various sensors used by these systems, and here are my thoughts:
Blindspot minder: Usually short-range radar or perhaps ultrasonic. Radar should have no trouble seeing the Aptera, and despite the curves' dispersive effect, I'd imagine ultrasonic should give a strong enough return. It's an open question whether the positioning of these sensors would allow them to actually pick up the wheel pods or just the main body, but they shouldn't be cutting it close enough to matter.
Figure some sports cars are so low to the ground they're probably not much taller than our wheel pods, so if they're okay, we should be okay.
Emergency brake assist: Front-facing radar in some cars, vision systems in others. Again, radar should be fine, since it'll pick up motorcycles and stuff too. But, the more I think about it, the more I wonder whether the vision systems' training has taught them that something Aptera-shaped is anything but a visual glitch!
I wonder if any other unusually-shaped vehicles have issues. (What about bicycles using a regular lane, especially enclosed ones -- any of 'em ever get rear-ended by a Tesla?)