Adobe Digital Editions 4.5.11

I just downloaded this software onto my computer because I have to use it for an eBook for one of my college classes, but it is SUPER SLOW! Like, when I try to scroll down the page, there is a long delay. It is especially bad on any page that is not exclusively text. Any page with coloring or graphics takes 30+ seconds to load, and longer the more graphics there are. I know that the problem is this crappy software because everything else on my computer runs quickly and normally. Is there any way to fix this problem or make the software load pages at an acceptable speed?