It is unusual that Audiobook Builder got hung up for that long. It would be great to be able to see a System Profiler/Information report so that we could figure out why the application is not performing as expected to there. Would you be able to send us one of those reports via email to
support@splasm.com? Just duplicate the issue in Audiobook Builder and then just after generate the report.
To generate the report, if you are on Lion, open /Applications/Utilities/System Information.app. Go to the File menu and select 'Show System Report'. Go to the File menu again after the report opens and select the Save option. Make sure you save the report to a place where you can find it, such as your Desktop.
If you are using something other than Lion just launch /Applications/Utilities/System Profiler.app and select "Saveā¦" from the File menu.
You can then attach the System Profiler or System Information report to the email to us and we will be happy to take a look at it.
As for checking on whether the program is still working, you could launch Activity Monitor, search for Audiobook Builder, and check to see if it says 'Not Responding' beside it.
To preserve your work you can save the Audiobook Builder Project and return to it later on. If you can cancel the build, just close Audiobook Builder and it will ask you if you want to save. Just tell it yes and then you can reopen the project later on from within Audiobook Builder by clicking on 'Open Existing Project' at the start.