X11 does not apply gamma correction, brightness, etc.
(colour curves) to the cursor. Blueshift have no effect
on the cursor. It does not seem to be possible to
listen for changes in the visible cursor and edit it.
This can sometimes be circumvented by disabling
hardware cursors in xorg.conf.

The colour curves are strictly independent, it is for
example not possible to swap red and blue, or adjust
a subpixel depend on another. It is to my knowledge
not possible to do so in X11.

VidMode can only modify the primary monitor.

Blueshift only support up to 64 monitors (per screen?).
If you have more please send be a photo of your awesome
setup and I will make sure to fix this.

Blueshift requires adjustable gamma ramps. It is
very rare that video drivers do not support this.