The simple answer is that anything we proofread it counted; anything we don’t proofread isn’t counted.
For example, references and text within figures are not proofread and should not be counted. We do proofread figure legends, so they are counted. We don’t proofread author names under the title, so they aren’t counted.
If you’re not sure whether to include something in your word count, please contact us and we’ll advise you.