I don't think there's a keyboard shortcut for inserting a no-break space, but
you can make one.
Insert a non-breaking space into some text on a slide.
Select JUST the space character and press Ctrl+C to copy it.
Now choose Tools, AutoCorrect Options and go to the AutoCorrect tab.
Under Replace, type (nb)
Type it just as shown, with the parentheses.
You'll see a little blue thingie in the "With" area to the right. Leave that
UNTOUCHED. PPT has automatically filled in the "With" text box with whatever
was on the clipboard ... a nonbreaking space in this case.
Click OK.
Now when you type (nb) PPT will replace it with a nonbreaking space as soon as
you type the closing parenthesis.
It doesn't have to be nb necessarily, but the parentheses seem necessary (other
punctuation characters might do as well but since PPT uses (c) and such already,
it seemed The Right Thing To Do.
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PPT Frequently Asked Questions
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PPTools add-ins for PowerPoint
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