Here is a fix from TPT: "If you purchased a PDF and it is blurry after you open it, solve it this way: on a MAC or PC, install the latest version of ADOBE READER. Then, open the file with ADOBE READER. That's it. On a MAC, make sure to "Open With" ADOBE READER and NOT Preview. If it's still blurry, that's because you are still opening it with Preview!"
I hope you have it figured out by now--sorry for the delay in response! :)