Noticed in the installed version of the MitkWorkbench, but happens in the built version as well. I checked that the search path is correct and points to .../MitkWorkbench.app/Contents/MacOS. MitkWorkbench is also located in this directory. However, the mdra* dylibs are still not recognized as MatchPoint algorithms.
We made some findings today that indicate missing dependencies of the mdra libs in the installer. Adding the ep/src/MatchPoint-build/bin folder to the search path works. So basically it is not enough to have the install rules in mitkInstallRules.cmake. Instead, the mdra-files should be handled like other plugins and passed to fixup_bundle as dynamic runtime libs.