I'm not sure but you may try editing all of the game files (in folder 'ff') using a hex editor (it's a bit painful to do manually when there are so many files. Also, don't forget to create a backup before you make the edits). When you open the file using a hex editor, you should see the text '2DKGT2G'. Change this to '2DKGT2K' (DO NOT CHANGE ANYTHING ELSE). If it is already '2DKGT2K' or the application still crashes after making the change to all of the game files, then I'm not sure what the problem is and would need more info(Eg: an error message if any before it crashes) to try and find a solution to it. Of course, I cannot guarantee that this would fix your issue or that I would able to definitely find a solution, but it could still be worth the shot.
Additionally, there are some video tutorials about 2D Fighter Maker on youtube that you could check if needed.