Complicated Problem with canvases and cameras

I'm trying to make a map editor... and I have a main canvas where I show all the stuff... but I also have some canvases for previewing some objects that are going to be placed...
It all works on until I show up the preview canvas... then it starts to draw it but somehow it also draws that convas on the main canvas...
Here is a screen shot

Here are some code that migh me helpful to understand

Function MainWindowCanvasRender()
	SetGraphics CanvasGraphics( MainCanvas)
	SetCanvasGraphics(MainCanvas,ClientWidth(MainCanvas),ClientHeight(MainCanvas),16,0,60)				
	cam.update()
	If Renderer_flat = 1
		UpdateObjects(5)
	Else
		UpdateObjects(4)
	EndIf
					
	CameraClsMode cam.cam,True,True
	Wireframe(False)
	UpdateObjects(1)
					
	HideEntity grid
						
	UpdateWorld()
	RenderWorld()
					

	'Second Pass
	ShowEntity grid
	EntityColor grid , 155 , 155 , 155

	If Renderer_wire = 1
		updateobjects(5)
	Else
		updateobjects(4)
	EndIf
					
	CameraClsMode cam.cam , False , False

	Wireframe(True)
	UpdateObjects(2)

	UpdateWorld()
	RenderWorld()
			
	'Third Pass
	If Renderer_points = 1
		updateobjects(5)
	Else
		updateobjects(4)
	EndIf
						
	CameraClsMode cam.cam,False,False
			
	HideEntity grid

	Points_mode(1)
	UpdateObjects(3)
						
	UpdateWorld()
	RenderWorld()
	updateobjects(5)						
							
	Flip
End Function

Function TexturesWndCanvasRender()
	Local g:Int = 0 
	For Local canvas:Tgadget = EachIn TexturesWnd_CanvasList
				
		Select EventSource()
			Case canvas
				SetGraphics CanvasGraphics(canvas)
				Local obj_tex:Tobject_texture = Tobject_texture(Object_TextureList.ValueAtIndex(g))
				Local scalex:Float = Float(GadgetWidth(canvas))/Float(ImageWidth(obj_tex.img))
				Local scaley:Float = Float(GadgetWidth(canvas))/Float(ImageHeight(obj_tex.img))
				SetScale(scalex,scaley)
				SetColor 255,255,255
				DrawImage obj_tex.img,0,0

				If obj_tex.selected = 1

					SetColor 0,0,255
					SetLineWidth(5)
					SetScale 1,1
					DrawLine(0,0,ImageWidth(obj_tex.img),0)
					DrawLine(0,0,0,ImageHeight(obj_tex.img))
					DrawLine(ImageWidth(obj_tex.img),ImageWidth(obj_tex.img),ImageWidth(obj_tex.img),0)
					DrawLine(ImageWidth(obj_tex.img),ImageWidth(obj_tex.img),0,ImageWidth(obj_tex.img))
				EndIf
						
						
				Flip
						
		EndSelect
		g = g + 1
	Next
End Function

Function EditTreeWndPreviewCanvasRender()
	Cls
	SetCanvasGraphics(EditTreeWnd_PreviewCanvas,ClientWidth(EditTreeWnd_PreviewCanvas),ClientHeight(EditTreeWnd_PreviewCanvas),16,0,60)
	'UpdateObjects(4)
	If CreateTreeWnd_Model <> Null Then ShowEntity CreateTreeWnd_Model
	CameraViewport (EditTreeWnd_Cam.cam,0,0,ClientWidth(EditTreeWnd_PreviewCanvas),ClientHeight(EditTreeWnd_PreviewCanvas))
	UpdateWorld()
	RenderWorld()
	'DebugStop
	'SetGraphics CanvasGraphics(EditTreeWnd_PreviewCanvas)
	
	'DrawText "Press Escape To Exit",0,0
	Flip
	
	
End Function
Function CreateTreeWndPreviewCanvasRender()
	Cls
	SetCanvasGraphics(CreateTreeWnd_PreviewCanvas,ClientWidth(EditTreeWnd_PreviewCanvas),ClientHeight(EditTreeWnd_PreviewCanvas),16,0,60)
	'UpdateObjects(4)
	If CreateTreeWnd_Model <> Null Then ShowEntity CreateTreeWnd_Model
	CameraViewport (CreateTreeWnd_Cam.cam,0,0,ClientWidth(CreateTreeWnd_PreviewCanvas),ClientHeight(EditTreeWnd_PreviewCanvas))
	UpdateWorld()
	RenderWorld()
	'DebugStop
	'SetGraphics CanvasGraphics(EditTreeWnd_PreviewCanvas)
	
	'DrawText "Press Escape To Exit",0,0
	Flip
	
	
End Function
Function SetCanvasGraphics(canvas:Tgadget,width:Int,height:Int,depth:Int,mode:Int,rate:Int)
	SetGraphicsDriver GLMax2DDriver(),GRAPHICS_BACKBUFFER|GRAPHICS_DEPTHBUFFER
	TGlobal.width=width
	TGlobal.height=height
	TGlobal.depth=depth
	TGlobal.mode=mode
	TGlobal.rate=rate
	SetGraphics CanvasGraphics(canvas)

	TGlobal.GraphicsInit()
	ClearTextureFilters()
End Function

UpdateObjects(5) is for showing some objects and UpdateObjects(4) is for hiding them