I've been doing some pretty extensive research on the problems with importing captions from Word in Captivate 5 (including a 2 hour tech support call), and here are my findings:
The problem seems to stem from copying and pasting within your Captivate project.
If you make a new Captivate project and insert a text caption, you can export the Project Captions and Closed Captions, make changes in Word, and re-import the captions just fine. However, as soon as you copy anything (press ctrl+V or select Edit > Copy) in your Captivate file or paste anything into your Captivate file, your file becomes corrupt and you can no longer use the Import Project Captions and Closed Captions functionality.
It's far from ideal, but the only workaround I've found is to NEVER COPY AND/OR PASTE if you're planning on using the exporting/importing Captions feature. The functionality breaks even if you copy and paste objects that don't contain Text Captions (e.g. shapes) so please be careful.
---
OS: Windows XP Professional 2002
Software: Captivate 5 & Word 2007
