You're supposed to follow the (8) instruction steps at the top of that page for registry entries, i.e. back up and then delete the Registry folders completely, starting with the Options folder for your version of Word. I didn't recommend reinstalling Zotero.dotm, as that is unlikely to help.
I know you didn't recommend (or mention) reinstalling Zotero.dotm, but I was trying anything that seemed somehow related... Thanks for reorienting me to the correct procedure. In that procedure they instructed to export and delete keys one-by-one so did that. I have great news to share--IT WORKED!!! After deleting all the keys in the Options folder (except the (Default).reg which can't be deleted), exiting the Registry Editor and starting Word, tested the various citations with diacritics and apostrophes and it worked like a charm--they inserted without generating an error; the citation font is as it should be and there's no extension of the field to the end of the paragraph that was part the problematic behavior of inserted citations with diacritics. Thank you so much @dstillman@adomasven@DWL-SDCA -- appreciate Zotero's support team's prompt replies and patience, + your Word expertise @adomasven is priceless!
@udonna Happy to hear it works. Thanks for working with us through this, we'll have another potential fix suggestion for other Zotero users that might run into this in the future.
Upgrade Storage
Thanks for reorienting me to the correct procedure. In that procedure they instructed to export and delete keys one-by-one so did that. I have great news to share--IT WORKED!!! After deleting all the keys in the Options folder (except the (Default).reg which can't be deleted), exiting the Registry Editor and starting Word, tested the various citations with diacritics and apostrophes and it worked like a charm--they inserted without generating an error; the citation font is as it should be and there's no extension of the field to the end of the paragraph that was part the problematic behavior of inserted citations with diacritics. Thank you so much @dstillman @adomasven @DWL-SDCA -- appreciate Zotero's support team's prompt replies and patience, + your Word expertise @adomasven is priceless!