What do you want to know? I use it a lot as part of my work (paed physio).
Its a standardised assessment, so it will give you a prcentile score that compares a child against other children his age. (The research for the test was done on a large number of children across the "normal" spectrum, ie it is not validated for use on children with physical disabilities.)
The checklist is done by parents or teachers, the actual assessment by a professional, usually physio or OT.
The results can be useful in that it can tell you whether a child needs therapy. But they need to be used withg caution.
A child with dyspraxia or similar will show up, but a child with behaviour, concentraion or language/communication problems will also score poorly. In my experience this has resulted in inexperienced therapists thinking that physio is going to help children who really need support from somewhere else.
There is a new version which came out this year, the Movement ABC-2 which I think is a little better, but it shouldnt be the only assessment that is done.
(If you attend the Dyscovery Centre that is unlikely to be the case, as they have everything on site to do a very comprehensive assessment.)
Hopethis is useful, but let me know if you need any more info!