Sometimes Adobe Captivate 3 and Adobe Captivate 4 behaves rather odd and some things that worked fine 5 minutes ago doesn’t work anymore. This can be anything from buttons, click boxes, inserted animations, text animations etc.
I have never found any real explanation to why this happens, but luckily there are some workarounds that will help you 90% of the time.
If something suddenly stops to work in your Adobe Captivate project then try and identify the slide where it goes wrong. If your buttons and project work until a certain slide is reached then that is most likely the culprit. Simply delete the slide and reconstruct it from the beginning again. Check if your project works now.
If this doesn’t work then open up a new instance of Adobe Captivate and open a blank project with the same dimensions as your original project. Then select all of your slides in the original project (easily done from the storyboard view) and right-click to copy. Switch to your new blank project and paste the slides into that. Check if your project works.
These two procedures has saved me quite a few times.