I was made aware that dzPrepBuild no longer works with .dof files. Since I don’t use it with Delhi 6 or 7 any more, I didn’t realize that myself. The bugfix was easy, just pass the correct parameter.
The new version is available from SourceForge. Note that, for whatever reason, SoureForge still claims that the latest download is version 1.3.0. You’ll have to select version 1.3.2 yourself. I hope that it is just a matter of time for SourceForge to update that link.