The best way to set a browser to use sproxy is via the included browserPAC file.
On firefox, you will need to open options by selecting Tools -> Options, then on the advanced tab, network subtab, click settings.
Click the automatic configuration URL radio button, then insert the following text. Change the port if neccisary (the 8888).
The below screen is of firefox, but you get the idea.
Ignore the url in the screen, it must be http://127.0.0.1:8888/pac
