To get Timezones API you need to update your backend as well.
As for images, it could be a bug. The path looks wrong.
Looks like it's seeking the wrong path, not looking in the modern folder, workaround by putting modern/images content in web/images
After running build_release & uploading to server I'm getting a 404 for images/icons & server/timezones
package.json is as per github, let me know if you need any more info.