When I have a project open, and I open any VI, project always links up to it, is there anyway to disable this?
I have not found a way to disable that yet but I have found a way to remove the link to the project. To remove it, just right click on the VI in the project tree and click on remove from project. Another thing that you can do is to create a new VI by selecting File>>New>>Blank VI and uncheck the box that says "Add to Project" . I hope that this helps.
This is an issue which should be addressed by R&D. It should be possible to have open one or more VIs at any time which have nothing to do with the project being worked on. Two use cases: (1). I am working on a project and want to write a little VI to test some concept, but do not want it in the project. The procedure you described above will work for this case. (2). I download a VI from the Forum to help someone with a problem. I do not want this "outside" VI to become part of the project. Only rarely would an outside VI be opened with intent to put it into the project.
I would suggest that the default behavior should be (1) new VIs are part of the open project and (2) an existing VI not in any project is not made part of the project when opened. If this idea gets any traction, I will post a suggestion on the New Ideas board.