When trying to start the Squish IDE the following error dialog may be shown:
This may happen only for older versions of OS X (it works on OS X 10.10).
This is caused by an issue in the built-in OS X unpacking tool, which incorrectly re-creates one of the files contained in Squish packages.
(More specifically: The file
bin/ide/jre/Contents/MacOS/libjli.dylib is being created as a plain text file containing a relative path instead of being created as a symbolic link pointing to the path
The solution is to delete the Squish package folder and then extract the Squish package again, but using a different extraction tool, for example The Unarchiver.