Some things you can try:
- Hold the Control key while opening the game
- Go to 'System Preferences > Security & Privacy', and change your options to allow apps downloaded from anywhere. https://support.apple.com/en-ca/HT202491
- Download the Windows version. Download the latest version of nwjs (http://nwjs.io/downloads/). Copy and paste the nwjs files into the Windows version folder, overwriting what's inside. Run the game using the executable in the nwjs files.
- Same as above, but use nwjs 0.45.6 instead.
- Download the Windows version. Download and install Wine + WineBottler. Run the Game.exe and library files through WineBottler to produce a Game.app. Run Game.app
- Run the game using the following commands:
chmod +x Game.app/Contents/MacOS/nwjs
chmod +x Game.app/Contents/Frameworks/nwjs\ Helper.app/Contents/MacOS/nwjs\ Helper
chmod +x Game.app/Contents/Frameworks/nwjs\ Helper\ EH.app/Contents/MacOS/nwjs\ Helper\ EH
chmod +x Game.app/Contents/Frameworks/nwjs\ Helper\ NP.app/Contents/MacOS/nwjs\ Helper\ NP
Otherwise, see if anything here helps!:
https://www.google.com/search?q=mac+stuck+on+verifying&rlz=1C1CHBF_enCA862CA862&...
Let me know if you find a solution!