Yes, actually I decided to take a look at the files to see if I could find something similar to the UE3’s ini file after rendering the light with the production settings. It is better than UE3 indeed, but I think it still not enough to reproduce details like precise indirect shadows. With the tweaks I can see some indirect shadows under the stair steps and get rid of some defective spots on plain white walls. Actually, with exactly the same settings I’ve used in UE3 ini, I still can’t get as many details. It looks like UE4’s lightmass is way smoother and artifacts free, but it is lacking details (maybe it’s just an initial impression).
I didn’t have time to mess with the new parameters inside the editor tough, I’ll make more tests soon.