They are segmentation faults. I'd recommend trying 3.4.1 and see if that
solves your problem:
http://www.libreoffice.org/download/
You can leave your existing Ubuntu LO in place.
Just download the .deb (including the help .deb). In nautilus, right
click on the .tz and select 'Extract here'. Then go to:
LibO_3.4.1rc3_Linux_x86_install-deb_en-US/DEBS in a terminal and:
$ sudo dpkg -i *.deb
Do the same for the help files:
LibO_3.4.1rc3_Linux_x86_helppack-deb_en-US/DEBS
After you've installed (again in the terminal):
$ cd /opt/libreoffice3.4/program
$ gksu gedit bootstraprc
Modify the following line:
UserInstallation=$SYSUSERCONFIG/.libreoffice/3
to
UserInstallation=$SYSUSERCONFIG/.libreoffice/3.4
Save the file & exit gedit. This will have LO 3.4 use the
~/.libreoffice/3.4 for your user profile and will not interfere with
your existing Ubuntu LO 3.3 at .libreoffice/3.
Again in the terminal:
$ /opt/libreoffice3.4/program/soffice
That will bring up 3.4.1 & you can try your .docx that crashes
immediately. Let us know how that goes. If if works, then you can create
an Applications|Office menu for 3.4.