Honestly, I've never heard anything about that, and to the best of my knowledge, no version of VERGE can do it. (Automatically, that is. You can always custom code it) There is a color tinting function planned for V2.7, and V2K and V2k+j have a ChangeAll function that could be used to create an effect like that, but it would have to be custom coded, as all it does is replace every instance of color 1 with color 2 in the given image.

Now that I think about it, if you are using the original 8-bit version of V2, and set up your palette very carefully, you could create exactly that effect, but again, it's custom coding. Basically, there's no way to just tell VERGE to palette blink/flash one specific image.

If you are just looking to flash them white though, (or any other solid color) you don't need to bother with palettes at all. There's a function called Silhouette() that renders all non-zero (non-transperent) pixels as the given color. Check your VC documentation, as most versions of VERGE have it, but I think it works differently in some.
(If you are using 2.7, it has no such feature at present, but the aforementioned tinting function will be able to replicate that effect.)

-Devon

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