Hi there! I understand you're experiencing an issue with not being able to move the letters in LunaCross. Let's see if we can resolve this together!

1. Check App Permissions: Ensure that the app has the necessary permissions to function properly. Sometimes, restrictions can cause issues with gameplay. Go to your System Preferences on your Mac, select "Security & Privacy," and check if LunaCross is listed under the "Privacy" tab.

2. Restart the App: Simply quitting the app and relaunching it can often fix minor glitches. Close LunaCross completely, and then open it again to see if the problem persists.

3. Update the App: Make sure you’re using the latest version of LunaCross. You can check for updates in the App Store on your Mac. Sometimes, bugs are fixed in newer updates.

4. Clear Cache: If you're able, try clearing the app cache. You can do this by going to the Finder, selecting "Go" from the menu, and then "Go to Folder." Enter ~/Library/Caches and look for any caches related to LunaCross. Deleting these might help.

5. Reinstall the App: If the above steps haven't worked, consider uninstalling and then reinstalling the app. This can resolve deeper issues that might be affecting performance.

6. Game Instructions: Make sure you’re familiar with the game mechanics. You typically need to drag letters to the correct tiles to solve the clues. If you're using a trackpad, check if gestures are set up correctly in your System Preferences → Trackpad.

7. Check for Updates: It might also help to check online for any known issues regarding the game at the moment or if there’s a patch/update available for this specific problem.

If you're still having trouble after trying these steps, please let me know! I can check for more specific information or escalate the issue if needed. Are you satisfied with the solution I provided?