[XeTeX] misplaced combining diacritical marks 2

[David J. Perry]

Alexander,

> If there is no pre-composed glyph xelatex _never_ assembles the glyph
> correctly.

This is just not true.  The example I sent you works correctly on my 
machine; I deliberately included y-macron-acute which does not exist in 
precomposed form in Unicode.

I need to run to work right now but tonight I will try your other examples 
and send a screen shot.  Meanwhile a very important question: are you on 
Mac, Windows, or Linux?  On a Mac, if you use a font like Junicode, things 
probably won't work.  Mac OS X defaults to using the native AAT font 
rendering system.  In order to get OpenType positioning features to work, 
you have to tell XeTeX to use the ICU renderer.    More later . . .

David