so your server IS starting up but you cannot connect to the GUI or you can't get it to run at all and your GUI isn't reachable as well? If your problem is the latter then try opening up the sites.ini file located in the ioGUI folder. Make sure the port listed is the same as your listening port that is also in your ioFTPD.ini file. Be sure to test out your listening port to see if it's open here:
http://www.yougetsignal.com/tools/open-ports/