WordsFlow 2.18 for Mac could be downloaded from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The software is included in Design & Photo Tools. The actual developer of this Mac application is Em Software. According to the results of the Google Safe Browsing check, the developer's site is safe. Despite this, we recommend checking the downloaded files with any free antivirus software.
From the developer:
WordsFlow solves the biggest headache in InDesign production: automatically merging changes in placed text or spreadsheet files into already-edited InDesign stories. It spares you the pain, frustration and errors of manually merging in changes from the external document. What's more, it works entirely invisibly, with no user interface beyond the normal link handling you're already used to for graphics.
You may want to check out more Mac applications, such as Cuadro or Resize Now, which might be related to WordsFlow.