Activation is very easy to do as you can generate the numbers anyway .. i wouldn't worry about that .
Heard from someone that did an activation recently, that after filling in the form he got a message that the fiscal number wasn't right OR the service was temporarily unavailable.
He couldn't find anything wrong with the fiscal number, but instead he found out that there are three final questions in the form, about allowing tivusat offers, offers of third parties, and statistical analysis on your data, that probably were the cause for the failure notice. After he allowed all offers and statistical use all went smooth..
You also have to add your emailadress, to complete the activation from the link in your mail, it seems.
So activation over the internet should indeed not be difficult, using the above procedure, for all those who want to watch Tivusat also....
Greetz,
A33