Persistent saving with sample editor

Can I save to disk edits I’ve made to samples? I’ve tried to export selected tracks but it throws and error: “The selected track types cannot be exported!”

If I try to Export Audio Mixdown I get: “The export range is empty. Please set the left and right locators,” none of which is explained in the manual. In fact, I used the example in the manual to get this error.

I like using this editor and I’d like to use it to clean up a large number of samples. In this case I’d like the edits to be persistent.

Any ideas?