ive tryed everything (well almost)
i have only printed in ABS
With glass on topp : i got best result With blue painters tape then lightly sanding it , and the a gluestick
and the best result using kapontape With a light layer of abs slurry on top, With out the glass plate (right on the alulinium)

bed must be 100 Level and the nozel shud be almost tutching the plate, so that the first layer is sqwesed/flatend. and the bed set to 100 (or even 110 if the temp isent true)