Trouble importing video

Hi there. I'm currently evaluating Captivate 9. I've opened a blank project and I wish to import a video. I discovered Captivate flat out does not accept .wmv formats, so I converted the video to .mp4 format using a separate software program. I then tried to import this video, and I received a message stating that Captivate needs to convert it to Flash format. I clicked OK. Three hours later it was still encoding the video, so I quit. I then read that Captivate plays well with .avi videos, so I once again converted the original video, this time to .avi using the separate software program. When I attempted to import this video, I again received the same message, and now another three hours later, it's still in the process of encoding it. Perhaps I'm not using the tool correctly. Has anyone experienced this? Thank you for your help.

PS. Bonus points if you can explain why Captivate needs to convert to Flash when it will ultimately be converting the finished project to HTML5. This feels counterproductive.