Issues with import of bullets and apostrophes

When exporting a Test Case from Zephyr, bullets and apostrophes are correctly exported as-is. The Export format is XLS.

When reimporting the export (but converted to CSV as that’s the only allowable import), Zephyr converts bullets and apostrophes to diamond question marks. The bullets and apostrophes are maintained during the conversion of XLS to CSV, so it seems like the issue is upon import to Zephyr.

Is there any way to prevent/fix this?