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 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 upto 64 monitors. If you have
more please send be a photo of your awesome setup I
will make sure to fix this.

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