tilemap offsets help?

I think I have found your problem:

simply change this:

Function place_tile()

	If MouseDown(KEY_MOUSELEFT)
		'Below we devide a map position by the tile size to get the correct place on the array
		map[MouseX() / 32, MouseY() /32] = curtile
		
	EndIf
	
End Function

to

Function place_tile()

	If MouseDown(KEY_MOUSELEFT)
		'Below we devide a map position by the tile size to get the correct place on the array
		map[(MouseX()-mapstartX) / 32, (MouseY()-mapstartY) /32] = curtile
		
	EndIf
	
End Function