I'm running Nuxeo 5.7.2, although I've been experiencing the same problems since 5.6.
When I install on Debian (7, Wheezy), as per the installation instructions, everything seems to work fine, but there is no preview button. I realise there were preview problems in Debian previously, but I wasn't aware the button could disappear, so I thought the function had been dropped from the system.
Just to check, I installed Nuxeo 5.7.2 on Ubuntu 13.04 (Desktop, not server), and it installs in the same way, but now there is a preview button when editing a file (with an 'eye' icon).
What does this mean? Is it that the installer (using apt-get) doesn't configure and start the LibreOffice listener correctly (a problem that I've been experiencing for years now, on OpenBSD, FreeBSD and Debian), so it removes the button altogether, or is there an advanced configuration option I'm not aware of.
For what it's worth, I set Nuxeo up on Debian with PostgreSQL as database, while on Ubuntu I just didn't have the time to waste (the installer fails to set up PostgreSQL correctly on both platforms, leaving the admin to fix the postgresql.conf manually, then start it up), using just the built-in database (H2?).
I'd like to know if there are problems on Debian that just haven't been discussed/fixed yet?
Thanks,
Sacha