>I will try PP. Thank you.
Dmitry,
There is an add-on for PPT that I believe will do what you want, I used only once a year ago for one presentation and I did not master it, just used the basics, but I believe it will do exactly what you want, see this quote:
Overview
pptPlex is an Office Labs experiment that uses Plex technology to give you the power to zoom in and out of slide sections and move directly between slides that are not sequential in your presentation.
http://www.microsoft.com/en-us/download/details.aspx?id=28558
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