Example: I'm trying to build huts with elderberry walls and birch roof. I've repeatedly double checked only one wood type is selected, but they mix all types when they build. I just keep making them tear down and rebuild until chance finally gets it how I want. I sit there and watch as they carry over birch split logs to rebuild an elderberry wall >.<

** This is only an issue with wood building. I've never had problems with any other material. My split logs are all in a single storage together, but so are my rocks, and they always pick the right ones out with those. It's also only walls and roofs with the problem, the floors are always right.

**** So I understand the issue now. You can tell them to use only, for example, elderberry wood LOGS, but not what type of SPLIT LOGS, when a build piece requires both types of material. That's why they ignore it. This should probably be fixed.