@mjmdvm

Hit F2 for preferences.

Under the tabs Startup and Scene you can set Daz to load a default file. I do that, I also set the file: right click on it (wherever you keep it) and General > Read only; tick the check box for: Attributes, Read Only. That makes it so you Daz can't accidentally overwrite it. If you want to ammend the default file you select to load, then just unckeck the read only option save and then set the attribute again.