1. A block becomes an attack when the player (s) attempting a block “swings” their arm instead of “intercepting” the ball (intercepting a ball using very little arm swing). This explaination can be found in the WIN! Wallyball Rules - Short Version.
2. 8.12 BLOCKING - To qualify as a block, the player must be at the net. “At the net” means in close proximity to the net (generally within approximately two feet of the net.)
3. A team in possession of the ball may cause the ball to bounce off their own back wall. The ball can then be played by another player on their team (as long as they are within the allowed three touches of the ball), or the ball can be bounced off the back wall in a manner that propels it over the net into the opponent's court. In this latter case, if the ball touches a side wall or the opponent's back wall before a member of the opponent's team touches the ball, a two wall violation occurs and a point will be given to the other team if the other team is serving, or, if the offending team is serving, a side-out will be called.
If the ball hits the 1st wall and then contacts the net before reaching the 2nd wall it is still considered 2 walls and the play is dead.