The game picker in Mondo Solitaire for Mac requires a minimum height of 800 pixels. If your display does not meet this requirement you will get an error preventing you from launching the game. You can bypass this requirement and play the game, though the game picker may be slightly difficult to use at times.
To override this setting, open Terminal in your Utilties folder and paste in the following command:
defaults write com.ambrosiasw.mondosolitaire IgnoreResolution -bool YES
defaults write ~/Library/Containers/com.ambrosiasw.mondosolitaire.mac/Data/Library/Preferences/com.ambrosiasw.mondosolitaire.mac IgnoreResolution -bool YES