Morse Runner is a Windows-based contest simulator developed by Alex Shovkoplyas, VE3NEA. Using Wineskin, it has been successfully and seamlessly run under OSX, and made available here for download. Sure, you could use Wineskin to do this yourself (and save me some bandwidth), or you can pull the ready-made dmg from here.
Running Catalina? Go to 'Download' to read the latest (and grab a box of tissues)
After downloading, open the file. Drag Morse Runner to your Applications folder. The application should run successfully without further configuration. Note: it will not curently run from within the dmg file, it will need to be installed locally. Optionally, the MorseRunner.ini file may be edited to customize some settings. Most (all?) of the settings within this file can also be set within the application itself.
If you wish to edit MorseRunner.ini, take a look at the OSX Readme inside the dmg.
Further details about the settings available within the application are documented in the OSX Readme. This file is nearly identical to the original Readme from VE3NEA, other than the OSX-specific installation and uninstallation instructions.
Confirmed working on: El Capitan, Mavericks, Sierra, High Sierra, & Mojave
MANY reports that it DOES NOT work on Catalina. It is very unlikely that it will work under Catalina in the near future, as it would require some pretty hefty development on Wine (they're working on it). The only other option I see is for some nice macOS developer to take the original code (it's open source!) and re-write it to run natively on 64bit macOS (go ask any developer, this is a lot of work). Since Xcode is now free if you're running Catalina, I'm happy to give it a try... when I can afford to buy a system that can run Catalina :)
If you have questions or comments about using this application under OSX, please email them to ki4stu k4iz at arrl dot net.