Applied to current GIT but not checked in:
1) 0013-Re_add-16-bpc-to-bccolors-scopewindow.patch(modifies scopewindow.C and guicast/bccolors.C)
2) 0002-Re-add-16bpc-support-for-color3way.patch(modifies plugins/color3way.C)
3) 0001-Fix-16bpc-direct-x11-crash.patch (modifies vdevicex11.C)
4) 0002-May-be-more-16bpc-crash-fix.patch (modified vrender.C)

Checked the above into GIT just now.

Not sure about documentation yet. Will you have some time at the end of the month for adding line or two about experimental. nature of this enable, and its limitations?

I did modify Configuration.tex to add the environment variable one liner already.

ANDREA: since you did a lot of testing, could you add latex documentation for the Manual as requested by Andrew? I can not decide where it fits in? and send it to me?