Stable update: 3D Camera; Timeline value tracks; Lots more!
Back again, got clues, but nothing as substantial to make a bug report.
3 layers.
"HUD" parallax 0
"Scroll" parallax 100
"BKG" parallax 0
Hud has a tiled image with effect "AdjustHSL"
That image is shown and works well in preview, but does not show in exported signed .aab and downloaded from google play as Alpha.
Hope it helps solving any bugs.