Gantt Project fails to open after repeated reinstalls

I’m using mac OS 11.6.1 on a 2021 MacBook Air computer. Initially, I was able to use the program, and when I changed the preferences (font size, appearance, etc) the program quit unexpectedly, and then I couldn’t open it. I’ve made multiple attempts to uninstall and reinstall, including erasing and redownloading all files, restarting the computer before reinstalling, installing the different versions of the app, and I still can’t get the app to open. It starts to launch and then quits/I get the “quit unexpectedly” message. Could this be related to compatibility with the most recent Mac software or hardware? Are there install files I haven’t found that could be causing lingering issues? I tried looking for files in the computer and user library folders but didn’t turn up anything. Any help is much appreciated!

Since you mentioned that you changed the settings, can you please open your Terminal and run this command: mv ~/.ganttproject ~/.ganttproject.bak ? Then launch GanttProject.