Publishing – How to open up a published work?

I published a project under BAK and my computer will not open it.  How do you open a BAK published project?  Is there another way to publish other than BAK?  Any help would be appreciated.  Thank you.

Assets? Where are they after the download.

I’m new to Adobe Captivate and I have been struggling.  I downloaded everything but the Assets are empty.  How can I view the Assets I downloaded?  Any help would be appreciated.