[XeTeX] Beginner: Devanagari problems

[Sven Siegmund]

Hello, good people,

yesterday I just started using the whole LaTeX thing, right away with
XeTeX. I downloaded MiKTeX 2.7.2960, part of which is XeTeX. (So I
think all versions of all my packages are the most current.)

I am facing problems with typestting Devanagari. In Texmaker, in the
UTF-16 encoded devanagari.tex document the Devanagari renders as this:
http://siegmund.szm.sk/latex/devanagari.png
(which is exactly as it should be)

when I run "xelatex devanagari" in the resulting PDF the Devanagari
sequencing is messed up and ligatures are messed up, too.

What am I doing wrong?

Here are my files:
http://siegmund.szm.sk/latex/devanagari.tex
http://siegmund.szm.sk/latex/devanagari.aux
http://siegmund.szm.sk/latex/devanagari.log
http://siegmund.szm.sk/latex/devanagari.pdf

Bst regards,

Sven