Setting up clksignal as the associated program for supported file types in your favoured filesystem browser is recommended; it has no file navigation abilities of its own.
Some emulated systems require the provision of original machine ROMs. These are not included and may be located in either /usr/local/share/CLK/ or /usr/share/CLK/. You will be prompted for them if they are found to be missing. The structure should mirror that under OSBindings in the source archive; see the readme.txt in each folder to determine the proper files and names ahead of time.
macOS
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There are no prerequisites beyond the normal system libraries; the macOS build is a native Cocoa application.
Build: open the Xcode project in OSBindings/Mac and press command+b.