Load Slice 10407, because without it, no easy way to define your own TransferMorph

You can have a look at the code attached, it defined a simple Spec UI (you can easily find the Morphic part in it),

and a subclass of TransferMorph creating a from the draggedItem to the mouse.

This Morph is usable in a fully Morphic UI, so it may interest you :)

(it's a pro to, so the code is not documented, sorry)