No that was not SPWN. You are talking about the incident with V-carnival that featured Calli and Sora right? That was another company (can't remember the name, I think it was a NicoNico subsidiary), and basically, from the get-go, as a foreigner, you were only able to buy tickets if you were from the USA/UK/Canada, which already pissed many people off. And then when the traffic got too much, they prevented new IPs from even just these few foreign countries to join the concert.