In “Single File” mode put a marker at the beginning and end of your file (press f8… the shortcut should be the same for as version as old as yours).
Add more markers to where you want the track splits, I assume about every 5 minutes.
In your Markers panel, select all your markers and make them range markers (click the icon that looks like this https://crl.ucsd.edu/~buff/audition/images/marker-merge.gif )
Select all your newly created range markers in the Markers panel and right click for “Export Audio of Selected Range Markers” and it will batch out the multiple smaller files.
I have Adobe Audition CS5.5 but the operation should be very similar to the manner I described it. Adobe hasn’t changed much of the core program, just built onto it.