Hi there! I understand your Flow Free app opens fine, but when you try to start a game by clicking on it, nothing happens. Let's get this sorted out together.

To start, could you tell me if you've tried closing the app completely and reopening it? On your Mac running OS X 10.15.7, you can force quit the app by clicking the Apple menu (top left), selecting "Force Quit," then choosing Flow Free and clicking "Force Quit." After that, reopen the app and try again.

If that doesn't help, please try these steps next:

1. Check for App Updates: Make sure Flow Free is updated to the newest version available on the Mac App Store. Sometimes, older versions can act up.

2. Restart Your Mac: A simple restart can clear up many temporary glitches.

3. Check for macOS Updates: Since you're on 10.15.7, verify there are no minor updates pending that could improve compatibility.

4. Reset App Preferences: Sometimes preference files get corrupted. You can try finding and deleting Flow Free preference files in your Library folder. For that:
- Open Finder.
- Press Shift + Command + G to open "Go to Folder" dialog.
- Type ~/Library/Preferences and press Enter.
- Look for files named like com.bigduckgames.flowfree.plist or similar and move them to the Trash.
- Relaunch the app.

If after these steps the problem persists, let me know if you see any error messages or if the app behaves differently. Also, please confirm whether this happens with every game level or just specific ones.

Would you like to try these and update me on how it goes?

The app opens with no problem, when I try to click on a game, nothing happens.