The following shortcuts are available:

F1: Help

F2: Server -> Start

F3: Server -> Shutdown

F4: Server -> Exit

F5: Edit -> Find

F6: Edit -> Find Next

F7: View -> Status Bar

F9: Tools -> Custom Command

F10: Open the top level menu bar

F11: Tools -> Nickname Blocker

F12: Tools -> Preferences

It is also possible to open your menu by clicking ALT+underlined key, so for example you can open the tools menu by clicking ALT+t you can then use the arrow to select the Migration menu since there is no F key shortcut for it.