I'm not sure if this counts as a true error, so I decided to post here instead of Github. I've been trying to get rid of a stack of errors like these at the very start of Rimworld's debug log, generated each time upon loading the game. From what I can tell the missing 'tech' references are related to HR (although they state techs from different mods and even base game vanilla).
These errors look menacing, but they might be benign as the referenced techs can still be learned by pawns.

I already tried moving HR around in my mod loading order, but the errors still show up. Maybe I'm missing something?

I also see a number of warnings: 'No relevant skills could be calculated for [Tech X]. It won't be known by anyone'. Can anything be done to fix that? The techs are 'VFEC_BronzeWorking', 'VFEC_RoadBuilding' and several 'Archotech' techs from SOS2.

I absolutely love this mod however, even if my pawns have to give up bronze for it!