DDS-60, is basically in PDF format and was created using Adobe Acrobat version 4; there are many PDF files.  You may find it convenient to have your web browser display the PDF files within your browser window using Acrobat as a "plug-in" rather than opening a separate Acrobat "helper" application.  The list of links below are Adobe support pages for configuring web browsers to display PDF files within the browser window.
A known problem in using the plug-in is that the Acrobat plug-in may stall when the user trys to naviagate too rapidly.

1.  Don't have Acrobat Reader version 4, download it here  

2.  Need Help Configuring Netscape Navigator for Windows to Display PDF Files

3.  Need Help Configuring Internet Explorer and AOL for Windows 95, Windows 98, and Windows NT 4.0 to Display PDF Files

4.  Need Help Configuring Internet Explorer for Mac OS to Display PDF Files

5.  Need Help Configuring Netscape Navigator for Mac OS to Display PDF Files

6.  Many Adobe Acrobat 4 problems are corrected by totally removing Acrobat 3 and re-installing Acrobat 4

7.  Adobe Support Database for other most common Acrobat Issues