It has you score each sunsection separately and then gives you a composite score. For example if the total points is 60-80 the child is seen to be an Excellent candidtate for a grade accel. and it is recommended. the next score would be a good candidate, accel. is still recommended, then on down the list. the lowest rating would be accel. not recommended, however consider other options such as enrichment or whatever.
If your child is excited about it, perhaps explaining things in a way she can relate to may be all she needs to help her understand (especially if she makes friends easily). I would say if she is OK with it, go for the skip fully. Is there ANYONE she would know in the other grades? Could she shadow a current child in the grade above so that she would have one person she knew when the skip takes place?
No book is able to tell you if you are making the right decision. You know your child best. Does your child handle change well? Sounds like if she is cool with the idea, she seems to have that much going for her. I would highly recommend googling everything you can about eh positive research regarding accel. or get yourself a copy of the book ahead of time. perhaps ask the school if you can review the book as it will give you a lot of insight. I think I would feel lost if I wasn't the one who had all of the information and research. There is a lot of information out there that can help you in your decision.