VMix works with absolute paths to the files in a project. This means that when transfering a project to another computer or if you duplicate a project-folder, the paths to files within that project have to be corrected. This is timeconsuming and ultimativly quite dangerous. I have been lazy lately not correcting the paths to local files within a project-folder, and my projects have files all over the drive from different projectfolders. Now if I would clean up the projects and move them to an archive, I would certainly have problems with missing files in other projects....

So to make things simple:
I would suggest that files in the same folder as the vmix-files or in a folder below the vmix-file should be stored with a relative path/filename. Every file that is higher up in the filehierarchy should keep an absolute path/filename, as it is now. In that way you could easily move a project folder, rename it, duplicate it without the hassle of "finding" files and tricking VMix not to find the old files and force a search-for-dialogue.
Savvy? Give it a +1.