Insufficient space

I imported a project/file to encore and encore encoded the project to the
largest file size possible. Then I tried to import another file, assuming encore
would retranscode. everything to make room for both files, but it didn't. Am I
doing something wrong? I was reading in the guide that encore will transcode to
the best possible settings to allow everything to fit on the disc, but I can't
get other files imported to allow it to do this. Do I have any options?

For some strange reason Encore is making me transcode the first file on import.
It won't let me revert the file once it is imported. =(