Save yourself some time and create an image group on Artstor and then export to PowerPoint. Much easier than saving all those images to your computer first!
Access your Groups and select which group you'd like to download.
Rest your cursor over Share and select Download Image Group.
Select either Request PPT (PowerPoint) or Request ZIP (Zip File).
It will say "Generating PPT/ZIP" but please note - when it stops, you will need to select Request PPT (or Request ZIP) a SECOND time, this time while holding down the Ctrl key (lower left of keyboard).
