Comment 2 for bug 707749

debian_support.Version is specifically for debian packages and not versioning of Debian, Ubuntu, <Insert other distribution here> releases which are not guaranteed to be valid debian package versions.

Here is an example of a .disk/info that breaks usb-creator:
Ubuntu "Warthog" - Build i386 LIVE/INSTALL Binary 20110127-14:42

FYI: In mangle_syslinux you look to see if .disk/info exploded using space as delimiter produces a list with a length greater than 2 before trying to extract the numerical version. This would work in this case as well if you didn't count everything after and including the dash character, ie. the comment.