The warnings you are getting mean that you cannot save VIs from the vi.lib for the previous version of LabVIEW. This is to prevent possible corrupting of the vi.lib VIs (VIs that show up on your palette) each time you use Save With Options.
Each VI you develop with VIs from the palette, will link to those VIs in the vi.lib. When you save the VI for previous version, it will try to link to the same VIs in the vi.lib of that other installation/version of LabVIEW. If the VIs do not exist in that version, or have different connector pane, the VI will not work.
Not all of the VIs in the warning list will be different in LabVIEW 6.0. You should check which VI doesn't work when you open your VI in LabVIEW 6.0, and try to make necessary changes. If the vi.lib used does
not exist in LabVIEW 6.0, you will have to use some other VI on the block diagram.
Zvezdana S.
National Instruments