After I have edited a track, when perform a ''File Save Active Track'' (MAC 10.4.6) the file is not properly created. In the console I receive the following error

CDSpinDoctor[881] DSSAudioFile: Error creating audio file
CDSpinDoctor[881] OS Status: kAudioFileUnsupportedDataFormatError

I have tried all file formats. If I save the file without edits it does save.....

Try dragging the active tracks to the desktop to see if that works. I once had a problem with SpinDoctor exporting tracks and it turned out the issue was my OS. You might try applying the OS 10.4.6 combined system updater on top of your existing 10.4.6 to see if that fixes the issue. Do you have another Mac or have a startup disk on a different drive to check if it works using a different system?

Thanks for the suggestions. I don't have another machine to test on. I tried dragging to the desktop and I receive the same unix file creation error. I have the latest updates applied. I didn't mention that this is not a file I recorded with Spin Doctor but an audio file. In addition to the file creation problem, if I try to play with Spin Doctor the edited file (within the application), the application hangs. The two behaviours are 100% reproducible so I think there is a fundamental problem somewhere~! Very disappointing as I only just purchased it and can't use it.....