Tested the latest NVIDIA driver – 352.63 – and it is OK with Kernel 4.3, and with the Fedora 23 version of the xorg server..
The only other ‘broken’ Fedora 23 items I have encountered are ffmpegthumbs and Samba.. I downgraded to the FC22 version of Samba
# dnf --showduplicates --allowerasing --releasever=22 downgrade samba*
….and – after a lot of unsuccessful testing and re-compiling – found a working version of ffmpegthumbs here: http://phobeus.de/tmp/kdesig/
So, my /etc/dnf/dnf.conf has the appropriate excludes, for the time being:
[main] gpgcheck=1 installonly_limit=3 clean_requirements_on_remove=true exclude=ffmpegthumbs* samba*
Robert Gadsdon. November 16, 2015.