If you want multiple VIs open at one time, one way is to a VI a VI template by saving it with a .vit extension. You can dynamically call a .vit any number of times and each time it will create a new instance. You can do a search for vit or look at the example
here.
If you just want one window open at a time, open the VI
You could then probably just use the Make Current Value Defaults method and then the Save Instrument method and save it as different name, though you don't want to do this for built apps.
If you're just looking for a means of saving various test configurat
ions, I think it's a lot simpler to open a single VI that writes the settings to an ini file that can later be recalled.