Hys wrote:
Hi
I know this problem or topic may already exist but i felt disappointed that such a problem has not been solved yet. Objects mirrored with emitter material don't work at all

I thought it would be solved in 1.5 maybe in next update maybe..
I've pulled my hair out with this issue too.
Try instance a full room of light bulbs, and notice that they share the emmiter output or just don't work. Ie, 4 bulb instances have 60/4 W each, or sometimes one gets 60/4 W and the other three are black.
Not too hard to collapse the lot before you render, but it's just managing that process all the time. The MXS output shouldn't even be seeing instance info imho, just pure mesh/material info.
Dave