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.
  A patch for X.org is available:
    http://lists.x.org/archives/xorg-devel/2014-April/041873.html
    http://lists.x.org/archives/xorg-devel/2014-April/041985.html
    http://lists.x.org/archives/xorg-devel/2014-April/041991.html
    For Arch Linux user, and users of deviations thereof, can install
      xorg-server-hwcursor-gamma from the Arch User Repository.

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.

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

VidMode can only modify the primary monitor.
It can potentially do adjustments on some video
drivers not supported by RandR.

Display servers cannot be started when DRM is used.

DRM disables Linux VT's colour palette on some machines,
which means that whilst DRM is in use, you will have
the default palette. Your custom palette is reinstated
automatically once DRM is not in use.