You can only run one Binder at a time because your user database locks while the Binder is running. If you cannot start up the Binder, and you receive a message in your console telling you that you do not have permission to write to your user database, it's probably because you have another Binder currently running.
If a File Type entry that you think is associated with a Binder entry is not showing up, it's probably because the Binder read in a duplicate of that File Type entry before it read the Binder entry in question. When there are duplicate File Type entries, the Binder only uses the first one it reads. The first File Type entry that the Binder reads does not necessarily correspond to the first Binder entry in the base window scrolling list. Therefore, you should use caution when using the Copy button to copy a File Type entry. If a File Type entry does not show up for a particular Binder entry, try to find and delete the duplicate File Type entry.