I am not sure about the CS3 version of Encore, but the 2.0 version will not allow you to even import a .PDF file, let alone set up a local disc link to that type of asset. The Blu-ray specification is supposed to allow for many new ways to access multimedia content, but I am not sure if it is implemented into Encore CS3 yet. This certainly would be an excellent feature request for future iterations of Emcore.
Only a handful of the Sonic products offer the capability for web links etc. (like DVDit, eDVD, Scenarist) or some other upper-end authoring solutions (Spruce DVD etc.). This might apply to linking internal files as well, not sure.
Also, as I recall, I believe that Apple’s laster versions of DVD Studio Pro also allows for this type of action, due to its scripting (programming language) abilities. I may be wrong on this, but I vaguely remember seeing that somewhere in one of my manuals or online for that app.
For our level of authoring, one thing that can be done is to create (or have created for you) a Macromedia Shockwave file that has an autoplay / autorun feature embedded in the ROM portion of a DVD.
Then, web links, audio, video and even links to local or remote PDF files are possible.
Shockwave is the older cousin to Flash and has been around in various forms since the 1980’s. Almost all of the enhanced CD’s that have bonus content use Shockwave, with a few exceptions found here and there. Flash also has the ability to accomplish what you are asking.
If you are interested in this, send me an e-mail and I will provide a link to an .ISO disc image you can download and burn of a project I created about a month ago for another videographer. It contains embedded web links, as that is all they wanted at the time, but a link to a local (on disc) .PDF file is a very easy feat to accomplish.
FYI, I have been programming in Shockwave Director since 1995 and have created dozens of projects over the years.
E-mail: scot “at” imgvideos.com