'Flash' Interactive Learning Toy

I need assistance in completing a Flash interactive toy that I have got to a point I can go no further with my current knowledge of ActionScript! It is a 'drag and drop' tray puzzle (flat 10 x 10 grid) which has strips of various numbers of cubes joined together, which fit into the base tray until it is full. I have a basic model working but am struggling getting the logic as to how the blocks drop into the tray if there is already one there and how to allow them to be dropped in multiple locations unless there is anothier block there already. Also I need to add a way of getting some feedback text to display under certain conditions. (e.g. if a block is put overlapping another one or if it does not fit in the tray it needs to have appropriate text to tell the user - also at the half-way point of comepletion and at the end it needs to bring some text up too. Again I have a rudimentary system working but it does not give enough flexibility. If you are interested in this project I can supply the FLA files and more detailed instructions. Please can you PM me and send some examples of what work you can do with ActionScript in Flash. Regards.