1 - Right to set up the Cache Light . Just repeat all the checkboxes. In principle, the same applies to anti-aliasing . Not necessarily, but Adaptive DMC can give hideous rash gray in the shadows and reflections and it is believed he was longer.
2 - Take away all IES. I can not imagine how you're going to see the reflective glossy tiles decorative "pattern" on the IES.
If you want to put it in principle IES Take away the VrayLight Plane. This is a completely unacceptable situation, when a light shines "in the back" to another. This is likely, as well as Use light cache for glossy rays and give those pesky artifacts in reflections.
If you go out of dark scenes with the IES alone, then do not hesitate to cheat their brightness as long as the scene will not be light.
In any case, I recommend that, in your situation, just set the spherical vireylayty in your lamps. This will make and "fill light" and will give the normal covenants and reflections on the walls. The main thing is just to lajty not stopped by the geometry of the luminaire.