Inkscape ha ricevuto dei dati aggiuntivi dallo script invocato. Lo script non ha riportato errori, ma questo potrebbe indicare che il risultato non è quello atteso.

Moving this report to the answers section because as far as I can understand (I don't speak Italian ;-) it is asking for help to install the python module 'UniConvertor' on Snow Leopard and not reporting a bug in Inkscape.

I'll try to answer in English what I understood to be your question... ;-)

1) As the error message tells, you need to install the helper application 'UniConvertor' <http://sk1project.org/modules.php?name=Products&product=uniconvertor> to be able to import/export CDR files in Inkscape.
2) Unfortunately there is no osx installer or dmg of UniConvertor available. You need to install command line tool and python module to your system Python using a command line setup routine (Applications > Utilities > Terminal).
3) first, download all the source packages needed (as mentioned on the UniConvertor download page <http://sk1project.org/modules.php?name=Products&product=uniconvertor&op=download>):
- python module 'Python Image Library' (PIL)
  <http://effbot.org/downloads/Imaging-1.1.6.tar.gz>
- python module 'ReportLab' package
  <http://www.reportlab.org/ftp/ReportLab_2_3.tar.gz>
- the UniConvertor source
  <http://sk1project.org/downloads/uniconvertor/v1.1.4/uniconvertor-1.1.4.tar.gz>
4) then follow the instructions on the Inkscape Wiki page how to compile and install python modules for each of the downloaded packages:
  <http://wiki.inkscape.org/wiki/index.php/Effect_requirements#Compiling_from_source>
  The Wiki page describes it for the already included lxml and numpy modules which you don't need to re-install. Just repeat the steps for each downloaded package individually and change the names of the modules accordingly. OTOH if you are on Snow Leopard you could install lxml and numpy as well because the ones included in 0.47pre4 don't work with Snow Leopards system python installation.

The alternative to use MacPorts <http://www.macports.org/> to install the python modules py26-pil and py26-reportlab isn't easier in the end, because as long as there is no portfile for UniConvertor available you'd have to compile that yourself anyway.

~suv (hoping that you find help to translate ;-)

(see also the discussion in <https://bugs.launchpad.net/inkscape/+bug/387946> comment #15 ff. about providing easier solutions for mac users and why they don't exist ;-)