[XeTeX] Font corruption (?) problem

[Karljurgen Feuerherm]

Hello,

I have a peculiar problem that's driving me crazy.

I'm using a MacBook Pro under Snow Leopard and MacTex, installed a few
months back.

I have a XeTeX source file (see below) which compiled fine, and
produced a nice PDF. I then copied four lines from the PDF and pasted
them into MS Word so I could run a character count. Word told me there
was a problem (Bad Font) with the font (Linux Libertine O) and that it
would try to disable the font.

Now, when I compile the source, everything seems to be bold faced...
though I've changed nothing in the source. So presumably the font has
been corrupted somehow... BUT...

This happened to me the other day, and deleting and replacing the font
with a fresh copy didn't help. I then created a new file using TeXShop's
XeTeX template and started changing it, a few lines at a time, to look
like my old file. This worked fine... until just now when I copied lines
into Word.

I don't see the font listed in the Disabled folder.

Can anyone tell me what's going on, how to recover most effectively,
and... how to prevent this from happening (I suppose don't paste into MS
Word is the obvious answer, but that shouldn't be a problem normally,
should it?)

Thanks

K
=====
%!TEX TS-program = xelatex
%!TEX encoding = UTF-8 Unicode

\documentclass[12pt,b5paper,onecolumn,twoside,openright,draft,leqno]{memoir}

%\usepackage[style=authoryear]{biblatex}					%
Adjust once understood; can't find biblatex.sty
\usepackage{bidi}							%
Bidi must precede xunicode.
\usepackage{multicol}
\usepackage[]{polyglossia}						%
Polyglossia loads fontspec, so no need to load it separately.
\usepackage{xltxtra}
\usepackage{xstring}
\usepackage{xunicode}

\setdefaultlanguage[variant=british]{english}					%
Follow UK rather than US standards.
\setotherlanguage[]{bulgarian}						%'Bulgarian'
is really Sumero-Akkadian ;)
\setotherlanguage[]{french}
\setotherlanguage[spelling=old]{german}					%
Use traditional spellings.
\setotherlanguage[]{hebrew}
\setotherlanguage[]{latin}	

\defaultfontfeatures{Mapping=tex-text,Numbers=OldStyle,Scale=MatchLowercase}		%
Scale is a safety feature to ensure that the various fonts look good
together.
\setmainfont[]{Linux Libertine
O}						%
Professional-looking font for body text
\newfontfamily\bulgarianfont{Linux Biolinum
O}					% Sans-serif font
for Sumero-Akkadian

\setxlvchars
\setlxvchars
\setlength{\textwidth}{\the\lxvchars}
\setlrmargins{*}{*}{2}
%\isopage
\checkandfixthelayout

% Define personal macros
\newcommand{\tdef}[1]{\textsc{#1}}
\newcommand{\bktitle}[1]{\textit{#1}}

\author{Karljürgen G. Feuerherm}
\title{Introduction to Akkadian\\using\\Late Larsa Texts}

\begin{document}
	\frontmatter
	\maketitle
	
	\include{Preface}
	
	\mainmatter
	
	\include{Grammar}
\end{document}