From fsi-language-courses.org (scroll to the bottom), the entire set of materials for the FSI Contemporary Cambodian course. I’ve only had a brief look at the introductory lessons but so far it looks pretty good (if oddly similar to the other FSI course and Modern Spoken Cambodian). It also includes the Khmer script for the dialogues and reading passages (unfortunately the audio is nowhere to be found).
Once again, sorry for the lack of updates, now that I have more free time I’ll be posting more often.