This works fine for me:
Graphics 800,600,32,2
SetBuffer BackBuffer()
Global x=200
Global y=200
While Not KeyDown(1)
If KeyDown(203) Then x=x-4 ;left
If KeyDown(205) Then x=x+4 ;right
If KeyDown(200) Then y=y-4 ;up
If KeyDown(208) Then y=y+4 ;down
Text x,y,"o"
Flip
Cls
Wend
End
Open in online IDE