Margins are not calculated properly unless the menu is in the default bottom right location

[MrCsabaToth]

This is because the main Container's transform: Matrix4.translationValues(16.0, 16.0, 0.0) does not take into account the alignment and always does the translation into one direction both axis. It should be transform: Matrix4.translationValues(16.0 * _directionX, 16.0 * _directionY, 0.0) instead. I'll push a fix.