Ugh, trying to replicate the issue I've found what was wrong.
I should have verified everything again before jumping to conclussions.
I'm very sorry for asking something that was incorrect on my part.
-----Please dismiss the incorrect question. Sorry.
I'm using basic lightning for this as the computer I have available right now is so old it can't manage advanced.
With that handicap I'm having this situation:
Let's say I have a wall and a window in it. I have a wall material and a transparent window material.
As the window is unpassable glass it has collision but I don't want it to cast shadow. So in the material editor I enable disable shadows for that material... but it still makes shadow even if I re-light the scene or save and reload the mission.
I would want that for invisible walls, too.
Am I doing something wrong, is it just a limitation of basic lightning or is it suppossed to work and something is buggy?
Thanks for your help.