I have installed the CSV Export Format Plugin, but I cannot get any meaningful data out.
After the install the “Browse Items” page shows “csv” as one of the Output Formats in the list at the bottom of the page. However when “csv” is selected, the file created only contains 3 bytes of data, non of which can be displayed. All the other Output Formats produce meaningful data.
This is the byte order mark of the utf-8 standard, so you probably do a custom change on the Omeka core, or on the server.
And if not, this is a bug in the plugin, so open an issue on github.