need a reliable converter for powerpoint to movie file

Try to follow these steps in order to do it manually:

First, select the transitions tab at the top of the screen.

Now, click on a transition option to preview the transition style.

Once you have determined your preferred transition, click on that transition before going further.

After that select the duration for the transition by typing a length of time into the duration box.

Now, select the method for advancing slides.

 Slides can either advance after a specified period of time which you can set by typing a time in the after box.

Or, by clicking the on mouse click option, you can set a custom time

Select the slide show tab at the top of the screen.

Now, click on set up show.

Then, customize the settings for your slide show.

  For recorded narration, make sure the show without narration box is not selected.

For used animation, make sure the show without animation box is not selected.

 If you want to create a video with only a few slides from your deck, select your preferred slides in the slides section of the set up show settings box.

 If you set timing for slide advancement, select use timings, if present.

Now, turn power point into video.

From the file drop down menu, Select the save as movie

Click on movie options from within the save box.

Following options will appear:

Movie Dimensions: 640 x 480 is the default size; you can also set custom dimensions, or select current screen size.

Media Settings: follow slide show settings, or none.

Background soundtrack: if you want to add a soundtrack for your video, this is where you select your preferred background music.

Optimization:  smooth playback, quality. automatic, size,

From above settings, you can choose to apply the settings to the current presentation, or you can choose to use the settings in all new presentations.

Finally, click on OK
 
Hope, this will help you.

When you say "slide transitions don't move properly," it's not clear what's happening. In addition to the known sound issue, there's apparently also a known issue with slide transition timing. See "Timing of powerpoint slide transitions is not working well." (Note: The URL is to a Microsoft TechNet site and requires login to access.) Briefly, one of the members tested slide transitions in multiple environments and found that:


This message was posted in 2016 and the most recent report of this issue is dated July, 2018.

One possible option is to use screencast software to capture the slide deck playback. Most video screen capture software does require purchase. Some offer free trial versions, but those versions sometimes include watermarks or restrict the length of the video capture.

Before looking into video screen capture software, though, it might be helpful if you post the PowerPoint slide deck. You don't need to post the complete deck if the problem presents itself when you create a video using only a subset of the slides. It would also help to know how you're creating the video. If you're already following the steps described by Alice Simpson, then we need to look at other options.

I didn't create the presentation - someone else did.  It consists of pages with photos that move and overlay, and music.
The movie is created successfully except one of the photo transitions doesn't complete as it should until the music stops and then it completes too quickly from there and in silence.  The final slides go back to working as they should.  Based on your feedback I tried Windows 8.1 with PP 2013.  Created both mp4 and wmv files, and they both still have the issue in the same place.  

AT this point I'd love to shortcut the solution using another product because I think PowerPoint is the issue here.  I've even tried on a Mac and the resulting movie fixes the transition issue but there is no sound!  I can't believe MS didn't include sound in the PP for Mac - but here we are.

Do you know of an effective reasonable prices screen capture software?

Maybe consider exporting the soundless video in PPT on the Mac and then add the sound in imovie.

Thanks Echo this could work, but I don't know how to add the sound?  The soundtrack is only available in the original powerpoint slideshow.

You can extract the sound using these steps: http://echosvoice.com/extract-pictures-video-and-audio-from-your-presentations-in-3-easy-steps/

Thanks Echo - your instructions reveal 13 .m4a files, which when listened to separately seem to comprise the sountrack.
Is it a matter of importing these end to end in iMovie, or are there silences between that will require resequencing of the silde deck?
I had hoped it would contain the entire soundtrack as a whole.  I know, I'm asking for easy when this clearly isn't.  Appreciate your help.

Yeah it's impossible to tell if you just need to lay them end-to-end or what. Ifthere's not silence in the presentation, then probably you can just lay them in to end. But it's really hard to say without seeing it. Sorry.

Thanks all for your input! Screen Cast O Matic solved this for me