How i make this, pick a variable from another object.

Hello I have a question here, I created a local variable to a block where when you place an object on the block arrow this vaíável to 1, otherwise to 0, it happens that when viewing the object "tower" which is just above the block, the continuous variable to 1, how i use pick to pick to up exactly each block to sell the tower and sets your variable property to zero.

If you know which block you mean and how you can explain this to the program, you have your answer..

The right block has to be referenced (picked) in the event/conditions or Construct2 will not know which one you mean..

It is because I created a w_wp name variable with weapon, weapon is the watchtower, if any tower on the block, then change the w_wp value to 1, if you are not I want to change to 0 at the time of create Object weapon1, and put on a w_wp block prevents that there are several towers in the same area of the block, it turns out that created a logic to the tutorial learning how to play my game, but in this case there is bug where the player can place a once a tower on top of another, which does not want to happen, and when I sell a tower after passing the tutorial, I am unable to put another tower on the site where there was another tower that was sold. I am not able to handle it.

Wouldn't setting the value back to the original value for each block after the tutorial work?