Couldn't you set Norton to allow Blockland through its own little "firewall"?
As soon as Blockland downloads and I double click on it blockland setup gets removed instantly. The only work around to this is if I turn off the firewall and then install, after that I can turn back it on and it will run fine. The problem however is that people new to Blockland will think that Blockland has/is a virus. This will automatically make buying a no no.