I have a model of Elevator with light inside of it (ENS Rect). It shines outside through the walls.. I thought that it could be an issue with it being inside of another component 2 levels deep.. but problem disapears if I Ctrl+X it and and Alt+E > A (paste it again in same lacation). it continues to be OK even after saving and opening again.. Looks like semi random error but it saves in model.. If I don't fix it it apears exactly the same after reopening.. restarting ENS Preview etc..
I had simillar issues with lights being close to some serfaces.. For example lights on the ceiling were lightning plants on the roof .. usually was enough to move them a bit away from wall..
and it behaves like it is actually shining up (which should be blocked by the lamp model) in the same time the same component next to section cut behaves as expected..
but with this rectangular it didn't matter.. it just ceeps to shine through.. tree different materials with no transparency.. One of lights inside of group other outside..
Can it be memory issue.. I'm on rather outdated hardwear..