Hello Andy and welcome to the forum.
The Skipton tests are the same tests as Ripon (but different pass mark!). From memory the NVR is 80 questions in four sections of 20 questions, each section is 10 minutes long and no going back once a section is completed. But I could be wrong, it's almost 2 years (eek) since my dd did hers.
The VR I really can't remember
, something like 125 questions, but Herman will be along shortly and put me right. If not I'll ask dd if she remembers when she gets in tonight. You can always ring the LEA in Harrogate, they're very helpful.
The top score you can get is 280 but as for standardisation, well, I think you need a degree to understand it, but rest assured your dd will be awarded the extra marks due to her age.