nPower and my UX nightmare

I saw npowers new Wallace and Gromit ads for their energy monitoring device.  Apparently just ask and you'll get one.  Brilliant.  After lots and lots of web searching and scratching of heads I found out the way to do it is register for a paperless billing (which I was already on) - this is of course once I'd worked out how to log in (tip: tiny link top left corner in a sea of red).  More confusion and then I find you just have to edit your details (it took me a couple of reads of the clearly written English to work this out):

To request a FREE smartpower electricity monitor, set up paperless billing, or activate other smartpower options, simply add or edit your account details now 

First, what's wrong here?  Do an ad campaign and then make it hard for existing customers to follow through? You'd at least thought that all you have to do is log into your account and see a picture of Wallace and Gromit inviting you to click the big Apply for Smart Power Monitor?  No?  Well, obviously the marketing guys at nPower don't think so.

But it gets worse.  I try to edit my details and the page blows up with a load of error messages about missing information.  But there's only check boxes, the stuff that's missing is your account details? Huh? There's no place to enter them either (and why do I need to enter something you should already know)?   So I try to re-register for paperless (I think I'm smart here, I'll disable it then re-enable it).  This time the fields it moaned about not being filled in are there and blank and apparantly I have to refer to the bill npower sent me for the details (even though they are all on the previous page next to the link I clicked to get here).  But it blows up, this time horredously, logs me out and gives me a 'sorry, our system appears to be experiencing problems'.  You don't say.

So I email npower to ask them to sort it out.  Explain clearly that the website keeps blowing up every time I try register for the monitor and ask them if they could just sort it out for me behind the scenes.  A few days later I get this reply:

I have lokked into this for you and customer do have to apply for the smart power monitor on line please follow the information below to apply ofyou still have issues please call our web support team direct on 08451663443.  

Did they read my message?  Did they read there's before sending it? Can they read?  They certainly can't write.  Great customer service nPower.  I feel really valued.  Well done.