Some of you may have read the WHFRP book Realms of Sorcery. Some of you might also remember the translation of Teclis words about creation. I never thought about it this way, but it may explain, why the chaos powers can rightfully claim the title gods.

The text says, that everything came into being, because nothing was and thus everything possible ( Which is quite reasonable) Now due to this creation and the multiverse came spontaneously into being along its principles including the law, that concepts, created by intelligence have an echo in the void and that those echos can fuse into its “citizens”.
This way, the warp would really be NOTHING, which would fit quite well the nickname “the Void”. It’s a place without energy, matter, information and law. Its, as Teclis called it, pure potential at a point before existence.

Since all the chaos powers and daemons are just lesser aspects of each other and the void itself they are GOD in a way and creation, its just, that gods own creations gave birth to his self awareness.

This would also explain, why there are several mentions of other dimensions in the Warhammer 40k universe ( see Codex Necrons) that still do not have an impact as the warp does.