Thanks for letting us know about this issue! I’ll add it to our bug tracker.
What version of FMOD Studio does this crash occur in? It doesn’t crash when I try it in version 2.02.10.
In the mean time, you can stop FMOD Studio from trying to open the last-opened project by manually editing its settings file. On MacOs, you’ll want to look in ~/Library/Application Support/FMOD Studio/Settings for a file called “Studio.2.02.00.config” (or possibly “Studio.2.01.00.config,” or “Studio.2.00.00.config,” depending on which version of FMOD Studio you’re using). In this file, look for a property called startupMode, and set its value to 0 (or just delete it). This will cause FMOD Studio to open the Welcome screen when launched, instead of trying to re-open the last opened project.