Can Captivate record this? Yes, it's possible to achieve
Will it track mouse clicks? Yes, if you use Full Motion Recording (FMR) it will record all mouse activity. But you cannot later edit mouse movements when recording using FMR. Additionally, auto-generated Text Captions will not be possible. (These are Text Captions Captivate adds for you to describe what was clicked and what happens)
Will it record voice? Assuming it's capable of recording system sounds I'm thinking it may be. If all else fails, you could insert a small patch cable between the Speaker or Headphones out and Mic in connectors to record.
The real question is to ask if Captivate is the best tool for the job. And in most cases it isn't. FMR is an awful way to record. You will find yourself frustrated.
Captivate is all you have to work with, you could do it. But I'd be looking at different tools if this is the type of recording you wish to do. Perhaps see if whatever is being used to present the webinar has a recording feature. Many of them do.
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Thank you so much! That answered my question!