well, since you got FF onto the computer that cant connect, you must have a way of transferring files between the two computers. therefore, just take the .ffxml file (which IS the filter) off the non-connected computer and move it to the one that can connect and upload it to the forums or send it to someone that can do the 'send to server' transfer and let them submit it for you. or, put FF on the computer that can connect (though i'm guessing you have a reason for not doing this).
obviously, if you just post the file on the forums you're not getting into the server queue, so i dont know how the devs would handle that but that seems to be the next question.
oh, and your 'my favorites' folder shld be in c:\documents and settings\[your user account login folder]\application data\filter forge\
craig
If wishes were horses... there'd be a whole lot of horse crap to clean up!
Craig