The Red Dot means:
1) Your Manual Price is higher than what Smart Pricing would put it at. Proof, keep dropping your price and the dot will eventually go away.
2) Your Smart Price has hit your Minimum, but unencumbered with your minimum, the Smart Pricing would price it even lower if it could. Proof, drop your minimum price until the dot goes off and you will see the algorithym suggested Smart Price. Put your minimum back up before someone takes advantage of an artificially low price.
(I still haven't found an explanation of this anywhere in the help section or the discussions. And you can not click anywhere on the dot or date to find this out.)
The Green Light Bulb means:
AirBnB has detected bookings that occured for that date that were lower than your price. If you click on it you will see a message on the right telling you how low other units have been booked for. (Of course you have no idea what kind of places those are. There is no indication whether they are comparing your 3 bedroom unit that sleeps 7 to a studio appartment that sleeps 7. Or in my case that they are saying the competitors are renting their units for $10/night. I still haven't found any documentation that explains how units are compared. There is a source that says the algorithym uses size, location, rating, beds, etc. But no document explains how. Imagine a getting a bank loan where the comps give you numbers but don't tell you what the homes are you are being compared to. Hosts need more information or we just need to abandon the Smart Pricing tool. I want to use the tool.)