TikZ in LyX - compiles, but acrobat says the pdf has an error [closed]

Question

I'm using LyX. I'm trying to use TikZ for the first time (to draw graphs, specically - trees).

The LyX code compiles and the pdf is created, but when I open the pdf, Acrobat reader says:

"An error exists on this page. Acrobat may not display this page correctly. Please contact the person who created the PDF document to correct the problem". The drawing does not appear in the document.

Here's my LaTeX preamble:

\date{}
\usepackage{tikz}
\usepackage{pgfplots}
\usepackage[compact]{titlesec}
\titlespacing*{\section}{0pt}{*0}{0pt}
\usepackage{colortbl}
\definecolor{lightgray}{gray}{0.8}

and here's what I wrote inside the TeX box in the LyX editor:

\begin{tikzpicture}
\draw (0,0) -- (1,0);
\end{tikzpicture}

I get the same error message in acrobat even if I remove the \draw line and only leave the \begin and \end lines.

EDIT: Here are links to my PDF and LyX files:

http://www.2shared.com/file/kqhal5As/example.html and http://www.2shared.com/document/0bwz3mrn/example.html

I am using LyX 2.0.0, MiKTeX 2.9, Acrobat Reader 10.1.1 (all in Windows). I am writing in Hebrew.