Hi Uwe,
I don't quite understand you. Maybe you could post a screenshot about those default settings. I don't find those settings in a SQL Server Project, as I don't have much experience on SQL Server Projects. If you want to change the connection, you could go
to the Project properties page:

And you can change all the related settings here. Not sure where "DefaultDataPath, DefaultFileprefix and the DefaultFilename(s)" settings are located.
By the way, this question is actually not about VS extensions. But i'm not sure where it belongs(maybe TechNet SQL Server forums). So I move it to [where is this forum for...] where the moderator may direct you to the right forum.
Thanks for your understanding.
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