Can I read content from external files?

My client has created more than 40 courses using Captivate 8. They need to add closed captions to all the screens. I know how to do this,screen by screen, in Captivate. I would prefer to automate the process by putting all captions into an xml file, read in the content and extract the caption that corresponds to a certain screen. Is there any way of doing this in Captivate?

Thanks for any suggestions.

Grace