DD is very slow with written work (and slow in general with ADHD) and it was processing speed that was below 100. She has been tested and doesn't have fine motor issues, but I'm not convinced that she doesn't have dysgraphia. DS actually has developmental coordination disorder and is getting an IEP for fine motor and his processing speed score is about the same as your DD.
Does anyone think dyslexia would cause a lowish Perceptual Reasoning score or a gap? I guess i haven't seen anything about that one way or the other, but it might make some sense if a child is looking at complex patterns. My kids have both displayed traits of hyperlexia (the neurological opposite) and they are both higher on PR than verbal.
One test you could ask about is the TVPS which tests visual perception. I don't understand their "she must have gotten bored" theory because I think testers usually alternate tests, for instance do a PR one, then a verbal one, then working memory, etc. rather than doing all verbal together, then all PR, etc.
