Umm, well considering you have a game to go with this editor, i'll try and explain how to place objects in game.
I'm a bit rusty on syntax(been in C++ lately) but i'll try and give you a quick rundown on what needs to happen.
-Well, 2D is much easier(for the mouse) so simply get the mouse_x,mousey when the mouse button is clicked.
-Next, use a variable that will count the number of, lets say squares for this example, that you want to make.
-If you planning on being able to make multiple objecs in this editor(which i imagine you are)set the variable to say 10 at first and give a maximum for it(say 100). That way you can set the next variable for the circles(or what ever) to 101 and max of 200 and the obj numbers wont conflict.
-Last, make new object(such as a set sprite or make object) and set the X,Y to the mouse_x,mouse_y you gathered from the click, increase the variable for the object number of the squares(to 11) and set it as the object number.
Again, im rusty on syntax so i cant give you exact words, but there is the jyst.
Hope it helps!(ill try and edit this post with some code)
