The Plug-Ins folder needs to be named "TDM Plug-Ins" and not "Plug-Ins". Apparently Digital Performer renames the folder after installing itself and its components into the DAE folder, including a later version of DAE and DSI. Another component it installs may also be Time Compression/Expansion, which can cause the system to hang while launching. Removing these elements, renaming the TDM Plug-Ins folder and verifying Mixer version 1.2 to be present should resolve the problem.