The Khmer writing system. Is it difficult?

I find it very difficult to pick up, and I have some experience studying languages with different writing systems (Greek, Korean, a smidgen of Mandarin). However, I have spoken to others who find it easy enough. As with all language learning issues, it's a case of effort, patience, and open-mindedness.

Unfortunately Khmer has no close relatives. Thai (and, by extension, Lao) has a different origin and while the alphabets may be related, the two are in no way mutually intelligible. Vietnamese is closer, but not enough to make a difference, and the writing system was based on Chinese characters until the French colonial authorities had it replaced with a Roman script (this seems to have been an anti-Chinese thing - if anything similar was even attempted in Cambodia it definitely didn't stick).

There does seem to be a stroke order when writing Khmer, but it is not observed strictly in everyday use.