I have just come across a problem where several of my Automator apps which worked with DTP 1.1.1 are broken in DTP 1.2.1 and OSX 10.4.8. These workflows used the action “Set Current Group.action”. They would hang during execution and also could not even be opened for editing.
After much trial and error, I found that opening the DTP package and replacing the 1.2.1 version of this action with the 1.1.1 version solved my problems.
I thought I would mention this and see if anyone else had encountered a similar problem.