Vivify's corporation color scheme may look perfect to me, it does not quite match the screen shots once installed in VIm 7.3.
To ensure that was not an error of mine, I went back on the website to realise there were two versions ; the one you see, yellow and blue, for GVIm and another, purple and red, for VIm. I opened the file and saw that colours are sometimes defined as "cterm". I guess this means that the same value will display different colours whether I run GVIm or VIm. This might have something to do with the terminal's color mode…
Too bad — my school will not allow me to use any other text editor than VIm or EMacs. And I definitely want this color scheme to work on VIm.
I checked CSApprox but, as the name (and the documentation) implies, it is a workaround with approximative results. I also checked CSExact but, as the documentation explains, it can be a source of issues.
I would really like to have corporate's GVIm colors on VIm. Is there any converter or way to manually convert the GVIm part for VIm ? Since Google is not my friend this time…
You've already found the canonical solution - CSApprox, which converts the 24-bit RGB values used in GVIM colorschemes to the nearest available color in a (maximum 8-bit) color terminal. CSExact tries to modify the terminal's color definition for exact color reproduction. Depending on the terminal and environment, this can just work, or be finicky.
I only know of one other option: Using a terminal that has full RGB support (I think it's in KDE's Konsole), and a Vim that supports that (I remember such patches being proposed; dunno whether it's already incorporated).
For me personally, the approximate solution by CSApprox is more than enough (I'm a programmer, not a graphics artist, and this is a text editor for heaven's sake), and it's easy to use (I use the static one-time conversion).