@ game maker man
Sorry I didn't reply right away. Positioning a 3D object with the mouse is not impossible but it's difficult.
This code snip is just to show you what your code is doing right now so you can see where it's really putting the boxes. (I increased the size a bit):
`load bitmap "face_tool.bmp",2
`load bitmap "mouse.bmp",3
autocam off
position camera 0,0,-1000
zcoord=1
i=1
tim=timer()
do
if upkey()=1 then inc zcoord
if downkey()=1 then dec zcoord
if mouseclick()=1 and timer()>tim+100
make object cube i,10
position object i,mousex(),mousey(),zcoord
inc i
tim=timer()
endif
loop