Hey Steve,
I added a server-side action to the CSV Creator last week. Still in Beta while some users are testing it but seems to be working well and is available if you upgrade the plugin to the latest version.
It’s very similar to the client side element but it’s not possible to return a file directly from the server so it simply returns the Base64 text. There’s a second action then ‘Create File from Base64’ that generates the file itself using the data API on your app. Set it up as shown here.
Hopefully this works for you!