Does the letterspacing (and tracking) options of microtype not work with the latest version of LuaTeX?
When I try:
\documentclass{article}
\usepackage[no-math]{fontspec}
\fontspec[SmallCapsFont={LinLibertineCapitalsO},
SmallCapsFeatures={Letters=SmallCaps}]{Linux Libertine O}
\usepackage[tracking,letterspace=500]{microtype}
\begin{document}\parindent0em
stealing sheap
\textsc{Stealing Sheep}
\textls[800]{\scshape Stealing Sheep}
\end{document}
I get error messages in my .log:
This is LuaTeX, Version beta-0.70.2-2012062812 (TeX Live 2012) (format=lualatex 2012.7.13) 10 AUG 2012 09:14
.....
! Package microtype Error: The `tracking' feature doesn't currently work
(microtype) with luatex.
......
! Package microtype Error: Letterspacing currently doesn't work with luatex.
See the microtype package documentation for explanation.
Type H <return> for immediate help.
...
l.18 \textls[800]{\scshape Stealing Sheep}
Run pdftex, or use the `soul' package instead.
microtype
; this is one of the significant changes over version 2.4. However, version 2.5 is still in late-beta ('beta08' as of May 2012) and must be downloaded and installed by hand. You may obtain it from, e.g., tlcontrib.metatex.org/cgi-bin/package.cgi/action=view/id=608.microtype
package and a version of lua(la)tex more recent than 0.62.