Since I don't own a Spectrum radio at all... I can't look at what updates are available, you can only see them for the radio's you've registered to download the updates for. I have read that you must register ( which you said you did ) to download the update for your radio since it is keyed to your radio's serial number. If it is keyed to that serial number, an update file you get somewhere else will not work for your radio. I'll try to post everything I've read about the process.
If true and just to make sure you are doing it properly... You would first register, then validate your email address after registering by clicking on the link in the email they would have sent you, then log in again with your account on your PC to download the firmware update for your radio. After downloading it, then copy the update file to your SD card, plug the SD card into your radio and then in the radio menu's, select the option to update the firmware. I have generalized some of that since I don't have access to their direct help and I'm just repeating what I've read elsewhere.
I mentioned logging in after validating your email address, it may not be required it may automatically log you in but... by doing it a second time, it make certain that your account info had been fully updated and you can get to the proper files. So it is a redundant step more than likely but doesn't take long to do so you avoid a possible issue with that step. Once you have logged in etc, I'd suspect they will list each radio you have registered so make sure to select the proper one in case you own more than one of the same model radio.
