I would like to add to the comment of "Lindashee".
1) An explanation of the controls is necessary because in addition to the standard W/A/S/D/Spase, the game also uses Shift (to create bombs that kill enemies), which can only be learned by accident.
2) I have nothing to add.
3) The character can jump while moving, but if he is standing next to a wall, the jump does not occur.
4) The platforms on levels 3 and 4 do not have collision, which makes it impossible to complete these levels.
5) I have nothing to add.