Slides from outline won't work that only brings in the text formatted as
headings (Heading1, Heading2 and so on. I guess your text title is the only
thing within your diagram that is formatted that way.
If you want that diagram (drawing) in PPT, you will have to select all the
different elements and group them using the drawing toolbar in Word. Click
on the drawing button, choose group on the top of the menu. But from your
reply I guess you have already done that. Once everything is grouped, copy,
go to PPT and paste it in. That's pretty much it. Once it is in PPT you can
still format it, if you want.
MVP - PowerPoint