Exporting to PDF - CS4 trouble

Question

In exporting my file, If I choose > Acrobat 4, (Acrobat 5 and above) I get missing elements to my PDF file (attached, v5.) pg 2 shows correctly, pg 1 doesn't (white box around text on left page is missing on the first page). At least v4 consistently works correctly for me (attached.) Of the 180 page book, only four pages print correctly, of the 74 pages that have this image applied.
The White Box is on the Master Page, so the same information is on both spreads.
This is the first time I've seen this, and I've been working from these files since InDesign 1 or 2. I'm thinking it's a CS4 bug, as CS3 was just fine. I've tried this with an older file (different fonts) and have the same results.
I can Print to PDF just fine, and then resize as needed for the web w/ PDF Optimizer (I've 'exported' this way to get around this problem.)
This file is exported as spreads, but same results if that isn't checked.
Anyone having similar problems? Any solutions?

Answer 1

This seems to be a CS4 bug.
It might be fixed with the lastest update, but you can fix it if you unlock the item from the master page, or flatten transparency when exporting to PDF (X-1a).It seems to only affect objects with applied effects on the master pages.But it doesn't affect every file.