I have a ACSM book I downloaded to my MacBook Pro from a digital library. I would like to read it on my ancient nook. What do I do to make this happen?

I clicked on the ACSM file and it opened the book, which I think means I'm screwed.

When I try to authorize mu nook, it pops up a cancer warning. At this point, I can't even get to the "authorize device" item under my nook's gear-icon -- that's greyed out.

Could Adobe make this any more difficult if they tried?