I tried out a number of explainer video applications (or applications that could be used for this purpose) and too many had fatal flaws. I wanted to use Camtasia as I have the application and love its ease of use. But I couldn't get the audio to work right. After two days of trying and working through help files (noting that others had similar problems), I gave up. But I'd like to use it again if I can figure out how to get the audio working.
I looked at other tools and tried them, but most had even larger fatal flaws. The one that worked immediately was Powtoon. There is a serious flaw: No ability to input a transcript for those who cannot hear the video. I'm looking for a workaround. (Let me know if you have one.)
When I bought Powtoon, I had to decide which upgrade to purchase. The higher versions had more objects, backgrounds, and background music. But background music should typically NOT be used in instructional video. The reason is easy to understand and quite clear. Added music makes attending to the important messages on the screen more difficult. In other words, it adds extraneous (harmful) cognitive load.
When people are learning, their mind has to select the important messages from what is shown and mix them with what they know to make meaning. This is. Hard. Work. Adding extraneous (extra) messages, images, and music makes this even harder. We absolutely should not do anything to make understanding harder.
You shouldn't use background music unless your lesson is about background music. If you want to understand cognitive load better, consider reading Write and Organize for Deeper Learning or Practice and Feedback for Deeper Learning.