I assign IDs to my lamps, in Render Settings I click on the pass numbers to enable them. So here's the weird thing: clicking on  makes all my lamps appear. Clicking on  makes none of them appear, despite some of them having an ID of '2'. If I don't enable light IDs action, clicking on  disables all lights in the scene. I'm beyond confused.
In Object Properties tab of the lamp I found this. No idea what it does and how it works.
As for the final light passes in a render, they come out exactly the same as in viewport. Any tips?