The size of PMI cannot be editted. It should print as it displays on the screen. You may want to submit a bug. You can do using the link at the bottom of this blog entry: http://blogs.adobe.com/mfg/2008/01/adobe_website_redesign_acrobat.php#more
Jim Merry, VP 3D PDF, Tetra 4D, jim [dot] merry [at] tetra4d [dot] com
Jim Merry, VP 3D PDF, Tetra 4D, jim [dot] merry [at] tetra4d [dot] com