Names like van Roojen
In the current Zotero 8, author name, e.g., Robert van Roojen appeared correctly as (van Roojen 2018) in the text body, but in bibliography appeared as Roojen 2018. I set the formatting to follow CMS 18, author-date style for anthropology specifically. This is a bug, yes?
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https://www.chicagomanualofstyle.org/qanda/data/faq/topics/Documentation/faq0363.html
This reflected CMOS17 14.21, indicating that bibliography entries can begin with a lowercase particle. That line has been removed in the 18th edition, but I am uncertain whether that reflects a change in policy. I'll write the CMOS team to find out what we're meant to be doing.
In your example, note that van Roojen must be filled in as the surname: you will then get "van Roojen 2018" in the citation but "Roojen, Robert van" in the bibliography.
For the du Maurier example given in the Chicago FAQ, the surname "du Maurier" will display as they show it if it is entered in quotes, as here:
https://www.zotero.org/groups/2205533/items/4PUL57BD