Looks like Prince doesn't support the complex scripts? I'm trying to find a solution to print Khmer Unicode...

Not yet I'm afraid; Prince 5.1 only supports languages that do not require shaping, such as Latin, Greek, Cyrillic and potentially Chinese.

However, we would be interested in expanding the language support in Prince, so if you know of any resources relating to printing Khmer that you think might be helpful such as fonts etc. feel free to post links!

http://khmeros.info/ This website provides you with lot of khmer unicode info... (also the sad fact that so far Khmer Unicode is only supported by MS Word and Publisher, which do not have the layout features we are after)

Khmer fonts you can find at http://www.khmeros.info/drupal/?q=en/download/fonts

Please, keep me up to date if you are planning to include this stuff!

It's been a long time coming, but the latest build of Prince supports the Khmer script!