@Ceencha – read about it there:
http://indesignsecrets.com/interactive-vs-print-pdf-in-indesign-adobes -frustrating-mistake.php
If you want both of the two worlds (working buttons and other interactive features) you have to:
1. export to Adobe PDF(Interactive) = first PDF file
and (here comes the trick):
2. export to Adobe (Print) = second PDF file
and THEN: replace all pages of the first PDF with the second PDF in Acrobat Pro (Document / Replace Pages…). All interactive elements (in this case your working buttons) will stay in place. What you'll get is a hybrid PDF of both PDF export worlds…
But to make that work best, use only EMPTY rectangles for button creation!
Uwe
