weird loopy jamming my app

You need to master something else first: uniformity. Every app you show here looks different in codestyle. You need to start simple and small, forget about games and other big stuff for a while. You can't learn a language properly if you put your focus on big stuff, and tomorrow you'll be looking at a mess if you don't add a bit of structure.

You could for example adopt this framework:

window=CreateWindow("bla",0,0,640,480)

;
;
; create more stuff here..
;
;

Repeat
	Delay 2
	WaitEvent()
	If EventID()=$803 quit=True
	
	;
	;
	; event-checks of the rest of the app
	;
	;
	
Until quit

;
; clean-up things like images, banks etc. *HERE*
;

SetBuffer DesktopBuffer()
End

Using that framework, here's how things can work:

window=CreateWindow("bla",0,0,640,480)

Global img=CreateImage(160,160)
SetBuffer ImageBuffer(img)
Text 0,0,"Structure!"
Text 0,32,"..please.."

Global canvas=CreateCanvas(0,0,640,480,window)

Repeat
	Delay 2
	WaitEvent()
	If EventID()=$803 quit=True

	evFunction()
	
Until quit

FreeImage img
SetBuffer DesktopBuffer()
End

Function evFunction()
	If EventSource()=canvas
		If EventID()=$203
			x=EventX()
			y=EventY()
			SetBuffer CanvasBuffer(canvas)
				Color x Mod 256,y Mod 256,128
				TileBlock img,x/4,y/4
				Rect 320-x,240-y,240,200,True
				TileImage img,x/2,y/2
				Color y Mod 256,x Mod 256,128
				Rect 320-x*2,240-y*2,120,100,True
				TileImage img,x,y
			FlipCanvas canvas
		EndIf
	EndIf
End Function

So, put all the eventchecking in functions .. they're sorted then, and shielded from everything else.