Other windows available through FTProofsheet are:
The Gallery window. This toolbar button is only enabled when a roll is selected. This allows easy browsing of all the images in the roll. There is no other functionality here; it's only to look and say "Awww, aren't they pretty?"
The Server Transcript window. This is accessible from the Tools menu. It shows the log of the communication between FTProofsheet and the server. The information may be useful for troubleshooting.