dragging issues, restrict items inside mc to stage and other problemss

[mgason]

Hi,
As this involves assorted dragging interactions to understand this explanation take a look at the file.
http://www.gasolicious.com/flashstuf...mouseMove.html
it should work like the last item on this page, called exploring kite interactive
http://www.hotmaths.com.au/FreeActivities/

I have a mc which includes 5 dots that can be dragged in various ways.
each one needs to be limited to the stage area when it is being dragged.

The limit should only apply to the dot when being dragged. If a dot being dragged causes another to exit the stage area that is fine.

I have tried a few ways, none work too smoothly.
One issue is that a dot which stops dragging at the edge can be hard to pick again.
Another issue is that if you drag really fast you can drag a dot offstage. This is usually when the top or bottom dot is dragged quickly from where it has stopped at the edge and the mouse is released just outside the stage.

FLA is attached, any ideas VERY welcome, not just to fix the problems either, got a better way to code it let me know!
Its not a lot of code, please take a look.
thanks
Mark