Create a batch file in your SSF folder and in that batch file put the following code:
@echo off
set game=%1%
set daemon="C:\Program Files (x86)\DAEMON Tools Lite\DTLite.exe"
set emu="H:\Emulation\Emulators\SSF\SSF.exe"
%daemon% -mount 0, %game%
start /wait "" %emu%
%daemon% -unmount 0
Modify the set daemon and set emu lines to match your program locations.
Now in Launchbox add or modify your SSF emulator if you already have it in there as an emulator and have it point to the batch file.
This will now work just like any other emulator, it will mount and unmount your image files automatically.