You probably noticed that playing back demos recorded on Nexuiz 1.5 won't work in 2.0 any more. The reason is that the maps got renamed.

However, you can convert the demos from 1.5 to 2.0 using this Perl script: http://svn.icculus.org/%2Acheckout%2A/nexuiz/trunk/misc/democonv-15-20.pl

To run Perl scripts on Windows, you need to install ActivePerl (http://www.activeperl.com).

To convert a demo, you open up a command line and type:

perl /path/to/your/democonv-15-20.pl infile.dem outfile.dem