Reaktor 4 no longer supports FreeMIDI or MAS for use with Digital Performer on OS9. These are old technologies no longer supported by MOTU as they move there development efforts towards Mac OSX and MAS/Audio Units on OSX. There are 2 options for using Reaktor 4 with DP3 on MacOS 9.2.2: 1. using the built-in file recorder to generate audio files to then import into you DP session. 2. use the 3rd party AudioEase VST Wrapper program to use Reaktor 4 as a VST plugin in DP. Although this is not a fully supported method of use.