Hi all A note for anyone running LyX on Ubuntu Feisty. If you are using mathematical formulae/formulas in your documents, you will need to to manually install the additional package 'latex-xft-fonts' on your system. This package *should* be a dependency of LyX but is currently only a 'recommended' package, meaning that you don't get it by default. Without this package your greek letters will show up as red text 'mu' or 'Delta' instead of as blue greek letters.
Hope that helps someone. Cheers JP PS: bug link is https://bugs.launchpad.net/ubuntu/+source/lyx/+bug/68971 -- John Pye Department of Mechanical and Manufacturing Engineering University of New South Wales, Sydney, Australia. john.pye AT student DOT unsw.edu.au