Ricardo,
Let me start by congratulating you for your KSP scholarship. I really hope it helps you in reducing the cost of obtaining your MSC at Sciences. I hope I have a decision soon too since I submitted my application few days to the closing date.
On CIUP, yes, I chose sciences po stage. I was also confused but it was the closest name to sciences po on the list although I must admit that my French is poor. Anyone with good french knowledge should help us out.
On the duration, I indicated interest to stay for a year however, since I am paying on a monthly basis, I can vacate the apartment when the session finishes. I think it finishes in May.
I chose family, others and employment for the sponsor of my accommodation since I had no scholarship on ground when I filled the form. I am still hoping to get KSP anyway. You can just register and mail them after completion of the registration. You can modify your info.
A facebook page will be cool