I was re-reading the sermons and this cought my eye at the end of sermon three. I can't work out anything doom-full from the sermon, does anybody know what it is saying?

The secret to doom is Vivec's prayer, which enshrines Love, which is unknown by the Dwemer.

So this sermon is also warning of the Red Year?

No. Vivec walked the way to escape mortal doom, by crawling into ALMSIVI's snatch, waiting for rebirth. And you can too.

The 36 Lessons have multiple levels of meaning, so what I'm going to say cannot used a a rosetta stone for interpreting the sermons. That caveat in mind...

Let the netchiman's wife represent Red Mountain, let the simulcarum represent Numidium, and let the egg represent the Heart of Lorkhan

The Dwemer recognize the power of the egg (the Heart) and so seek to cut into the netchiman's wife (Red Mountain), and create a simulacrum which can hold the power of the egg (Numidium). The doom of the Dwemer, and the doom of the old (pre-Tribunal) world both revolve around the power of the egg.