objects not supported in SWF output format on my Captivate project

[#1]

I'm using Captivate 2019 release 11.5.1.499 on my Macbook Air running Mojave version 10.14.6. I'm creating a project from PowerPoint and I've added an extra blank slide that I'd like to play a YouTube video on. I go to the Media drop down and select "Video" and then "Slide Video". I add the url for the YouTube video and click Ok. The video looks good on the slide and the audio plays as I would expect. Then I go to the Publish drop down and select "Publish to Computer". From there I change the top option from "HTML5/SWF" to "Video" and click publish. I immediately get this error:

A few slides or objects in the project are not supported in a SWF output format. The project will be published without the following unsupported items:

1. 360 Slides
2. Slide Video with overlay slides
3. Youtube or Vimeo Videos
4. Image as Button
5. SVG as Button

I click OK and the video saves without the slide I added that includes the YouTube video. 😞

Any suggestions or advice?

Thank you! 

Marci

[#2]

Publishing an eLearning course as a video has to first make a stop as FLV format which is a Flash-based format. You cannot embed a YouTube video as Slide Video in Flash-based projects (even if it's just temporary). It's probably due to the fact that slide video coming from YouTube doesn't really encode the video as part of your project. Publishing to video would never work in this circumstance.