Sorry for the late reply. Communication breakdown on my end here.
If you are still having difficulty, then do the following:
1. Launch "Terminal". This can be found in the following directory:
Hard Disk -> Applications -> Utilities -> Terminal
2. At the prompt, enter:
sudo launchctl stop com.filemaker.fms
3. See if the FileMaker Server folder has been removed from:
Hard Disk -> Library -> FileMaker Server
If not, then move it to the trash and empty the trash.