A new CDE version was recently released today: 2.2.0d.
They are considering CDE to be "beta" quality now. Apparently it is known to work well on at least Linux, FreeBSD, and OpenBSD these days. From the release notes, it looks like they have also added some basic Xinerama support for multiple monitors.
Code:
# 2.2.0d (beta) 05/30/2013
- We are being bold this time, and promoting CDE to Beta.
- More work on dtinfo. It now mostly compiles but is not quite ready for prime time. It is not built by default.
- dtksh now builds on linux systems.
- We do not build Motif man pages anymore.
- X11 screensaver extension support now works in dtsession on Linux.
- Some screen locking issues on the BSD's have been fixed.
- /usr/sbin/sendmail is now the default mailer on OpenBSD
- Basic support for Xinerama has been added to dtlogin and dtsession using a new DtXinerama library.
- Resolve many more compiler warnings
Unfortunately I haven't been able to get it working properly...? Upon starting an X session, I just get the copyright screen and an xterm. Sad face...