Placing image button on top of background image

[Sintek]

Hello there Forum Members...
I have been developing in VBA for 10 years...My first time delving into python...Total Newbie...
The reason for me doing this is the need to convert my VBA Windows Operating App I developed - see below demo - into an Android App...

I'm trusting this can be done...
demo

I have just started...
I am wanting to add images as buttons to an already existing background image being the main screen...
Making use of Kivy & kv file

class EzImage(BoxLayout):
    pass
class ToTSlider(App):
    def build(self):  
        #return Builder.load_string('ToTSlider.kv')     
        return EzImage()  

# kv file
<EzImage>:
    BoxLayout:        
        Rectangle:
            source: 'Images\main.png'
            size: root.width, root.height
            pos: self.pos
        # Here I am wanting to add a button on top of main image
        Button:
            source: 'Images\launch.png' 
            size: root.width, root.height
            pos: self.pos      

Edit...I tried another approach...Also not working...

class BackGround(BoxLayout):
    pass

class ToTSlider(App):
    def build(self): 
        # This snippet adds my 3 required buttons...  
        EzImage = BoxLayout(orientation='horizontal')  
        btn1 = Image(source='Images\launch.png')
        btn2 = Image(source='Images\print.png')
        btn3 = Image(source='Images\leave.png')       
        EzImage.add_widget(btn1)
        EzImage.add_widget(btn2)
        EzImage.add_widget(btn3)
        # Cannot get background in...it is either or...
        return BackGround()
        return EzImage
# kv file code
<BackGround>:
    BoxLayout:
        canvas.before
            Rectangle:            
                size:self.size
                pos: self.pos
                source: 'Images\main.png'

Can I please get direction...Google has rendered no results...

[Sintek]

So...I played around today and finally got this figured out...
Step 1 down...Lotsa steps to go...

Home = """
<EzHomeScreen>:
    canvas.before:
        Rectangle:
            pos: self.pos
            size: self.size
            source: 'Images\main.png'                
    FloatLayout:
        Button:
            background_color: 0, 0 ,0, 0
            size_hint: .32, .046         
            on_press: root.leave() 
            pos_hint: {'center_x': 0.18, 'center_y': 0.165}   
            Image:
                source: "Images\leave.png"
                center_x: self.parent.center_x
                center_y: self.parent.center_y
        Button:
            background_color: 0, 0 ,0, 0
            size_hint: .32, .046         
            on_press: root.print() 
            pos_hint: {'center_x': 0.50, 'center_y': 0.165}   
            Image:
                source: "Images\print.png"
                center_x: self.parent.center_x
                center_y: self.parent.center_y
        Button:
            background_color: 0, 0 ,0, 0
            size_hint: .32, .046         
            on_press: root.launch() 
            pos_hint: {'center_x': 0.82, 'center_y': 0.165}   
            Image:
                source: "Images\launch.png"
                center_x: self.parent.center_x
                center_y: self.parent.center_y
"""

Builder.load_string(Home)

class EzHomeScreen(Screen):
    def leave(self):
        print('leave pressed')  
    def leave(self):
        print('print pressed') 
    def leave(self):
        print('launch pressed')
pass


sm = ScreenManager(transition=FadeTransition())
sm.add_widget(EzHomeScreen(name='EzHome'))


class ToTSlider(App):
    def build(self):
        return sm