Thank you for your post.
Boot up your machine and do not launch any other applications. Then, launch FileMaker Pro. If this works, then one of the other applications is conflicting with FileMaker Pro. If this doesn't work, then deactivate, uninstall FileMaker Pro, and install on another machine. If this works, then there is a problem with your system. If this doesn't work, then you may have a bad copy of FileMaker Pro.
Please continue to keep me updated.
If you start a Mac with the shift key down, you will start in Safe Mode.
There is a harddrive test done and third party extensions are not loaded and added fonts are not loaded.
Starting up into Safe Mode does several things
The next step would be to install AppleJack and run it, it is more aggressive in cleaning things up.
The next step would be to create a TEST user with Admin rights and login as TEST to check if the problem is system wide or limited to original user.
There are troubleshooting tutorials here