[XeTeX] xetex-microtype font config files

[Stephan Hugel]

Hello,
I'm currently testing MacTeX 2010, and with it, the supplied version
of xetex, as well as the xetex-microtype package posted here in May.
Glyph protrusion seems to be working fine with the supplied Charis SIL
skeleton .cfg. Some (broad) questions:

Where can I obtain information about preparing config files for other fonts?
Are there existing (compatible/semi/compatible/etc) font config files
for the standard microtype package? Where might I find these?
Can these files also be used to configure tracking/kerning/spacing etc?
Is there an existing project to prepare these files?

--
sth