Bit of a fringe issue with a workaround:

"Call of Cthulu - Cults" is a large Lovecraftian-focused mod allowing the colony to worship elder gods in exchange for power. Many of the mechanics are gated behind founding a cult, which relies on raising a modded-in "cult-mindedness" pawn-need to a certain threshold by researching occult research options using the base-game research system.

"Research Reinvented" (abbreviated to RR) replaces the default research system with a wider selection of different research activities. As this is effectively a different research system entirely (even if the 'basic research' type is functionally identical to the base game), cult-mindedness is not coded to increase when using the modded research activity, making it impossible to start a new cult with RR active.

A possible workaround is to disable RR until you start a cult, then re-enable RR once you are able to increase cult-mindedness with sermons, though it should be noted that the "Study Successful Cults" research option will not work properly with RR active.