switching versions issues

[pierre-philipp braun]

Hi there,

I just switched to version 2.1 beta2 to test a layout script, saved the 
document, and when I try to read it with version 2.0 again, I get an 
error related to the LyX format.

path\to\tmpdir\Buffer_convertLyXFormat.emxxxxx is not a readable LyX 
document.

Aren't LyX document supposed to be readable by various LyX versions?  In 
that case this is definitely a beta.

Is there a trick to fix the document or should I look at my last backups?

thanks,
pierre-philipp