Hi there! I understand you're experiencing a black screen issue with the Wood Block app game on your Mac running OS X 10.15.7. I'd like to help you get this sorted out.

To get started, could you tell me a bit more? For example:
- When does the black screen appear? Is it right when you launch the game or after some interaction?
- Have you tried restarting the app or your Mac already?
- Are you running the app from an official source (like the App Store)?
- Has this issue started recently after an update or change?

This info will help me guide you better.

Meanwhile, here are some general troubleshooting steps suited for your Mac setup:

1. Restart the App and Mac
Close the Wood Block app completely. To ensure it’s not running in the background, open the Activity Monitor (found in Applications > Utilities), look for anything related to Wood Block, and quit it. Then restart your Mac. Sometimes a fresh start clears temporary glitches.

2. Check for App Updates
Open the App Store and check if there’s an update available for Wood Block. Developers often release patches for bugs like black screens.

3. Update Your macOS
Although you are on 10.15.7 (Catalina), make sure your OS is fully up-to-date with the latest security and performance fixes via System Preferences > Software Update.

4. Reset Cache / Temporary Data
While Mac apps may not have a simple “clear cache” button like mobile apps, quitting and relaunching the app may help. If the app stores data in a folder like ~/Library/Application Support/WoodBlock (check if such exists), you can try moving that folder temporarily to see if it resets the app behavior.

5. Graphics Settings
If the app has a settings menu, try lowering graphics or resolution settings. High settings can cause rendering issues leading to a black screen.

6. Reinstall the App
Delete the Wood Block app by dragging it to the Trash. Then reinstall it fresh from the App Store. This can fix corrupted files that cause black screens.

If these steps don’t help or if the issue behaves differently than above, please let me know with any additional details, and we can try a deeper look.

Are you satisfied with this initial guidance? I’m here to help you get back to gaming smoothly!