WG602 a MAC ADDRESS != 00

I was having the same issue with Firmware Version 1.7.16 (v.1). I could not find any way to back up the config file and could not ftp into the access point. So I pulled up firebug in firefox and found the following code:

function do_add() {
    if(getaccmode() == -1) {
        return false;
    } else if(getaccmode() == 0) {
        alert("Access control is Disable. MAC address will not be added.");
        return false;
    } else if(document.add_del.new_acc_mac1.value == "" ||
        document.add_del.new_acc_mac2.value == "" ||
        document.add_del.new_acc_mac3.value == "" ||
        document.add_del.new_acc_mac4.value == "" ||
        document.add_del.new_acc_mac5.value == "" ||
        document.add_del.new_acc_mac6.value == "" ) {
        alert("Incomplete MAC address!");
        return false;
    } else if(document.add_del.new_acc_mac1.value != 0 ) {
        alert("Invalidation MAC address!");
        return false;
    } else {
        location.href = "cgi-bin/saveacc?new_addr="
        + escape(document.add_del.new_acc_mac1.value + ":"
        + document.add_del.new_acc_mac2.value + ":"
        + document.add_del.new_acc_mac3.value + ":"
        + document.add_del.new_acc_mac4.value + ":"
        + document.add_del.new_acc_mac5.value + ":"
        + document.add_del.new_acc_mac6.value + " "
        + getaccmode() );
    }
    return true;
}

So I just entered directly into my URL:
http://192.168.1.2/cgi-bin/saveacc?new_addr=84:01:25:C3:C9:12%202

192.168.1.2 = IP of Access Point
84:01:25:C3:C9:12 = new MAC address to add
%20 = escaped space
2 = accmode (2 to allow)

It popped up a brief "Saving..." then gave an unframed listing of the MAC list.