This mod modifies the data of death screen.anm2, giving that look to the death screen. It makes some layers invisible and modifies others.

The problem with this is that apparently, this same data is requested by other things, such as the Bestiary, the Dream Catcher animation and the Lemegeton objects, etc., causing errors in them.

LayerId="3" - Breaks Dream Catcher bosses offset.
LayerId="5" - Breaks Bestiary offset.
LayerId="6" - Breaks Lemegeton Items and Dream Catcher items, making them invisible.

I don't know much about this game's engineering, lua or anm2 but I don't think the mod itself is poorly made. I'd say the blame is on the developers, who thought it was a good idea to use the death screen data on these other features.

I like the mod, so if I have time, I'll try to find a way to figure out how to fix the problem. Maybe in 30 years :)