What is your operating system?
The downloads are opening in 32-bit mode.
Of course they open in 32-bit mode; Adobe Reader and the plugin are still 32-bit. You cannot use a 64-bit browser to view PDF documents in the browser.
Sorry mistyped yesterday. Adobe is set at 32-bit and will not open pdf files. My operating system is version Mac OS X 10.7.3. I have not been able to open any pdf documents since adobe's update last week. Adobe is set at 32-bits always has been.
Sorry, I cannot help with Mac OS. Hopefully someone else here has some knowledge in this area.