Thanks for the explanation and help, I will wait to see what you'll come up with! :)
OFF TOPIC: (hope I will be able to apply the UNDO/REDO system to this)
I used a different Drag n Drop solution for selecting Objects with much simplistic way for now, so my code will probably won't fit to what you're doing since you'll do it based on your previous code.
My Drag n Drop solution based on a "Pan_Tool" object that have 3 modes:
1st Mode is turning OFF (invisible) the tool
2nd Mode is MOVING ALL instances on the layout
3rd Mode is MOVING ONLY selected instances (based on SetColor) so all the colored can be moved.
For now I press 'SPACEBAR' to change (cycle) between the modes if I need to move more than 1 instance.
This simple "Pan_Tool" is always centered on the layout, After I Drag it to anywhere and DROP it, it will get back to the center. I know it's not the most efficient way but it was the only creative way I could came up with for a very simple code that my brain can actually understand.
Back to Topic:
I hope that I'll be able to follow it and apply it to my code even that it is very different.
Thanks ahead for your kind help AllanR!