Sitefinity 3.x needs the Default Website to be present. Since you have deleted it you can set up Sitefinity projects using the Sitefinity Project zip file which you can download from your account and follow these instructions
the Telerik team
Do you want to have your say when we set our development plans?
Do you want to know when a feature you care about is added or when a bug fixed?
Telerik Public Issue Tracking
system and vote to affect the priority of the items