Sorry Tom, not buying it.
I can't believe that someone who owns this game can't understand what the 'point n click+hold with a pickaxe' action does. Even if you are new, when you've done it once isnt it obvious that it's a tad detrimental to whatever structure you hold the button down on each block for?..
You may not have realised that you weren't allowed to mine away at other peoples blocks, which would also suggest you didnt read any rules, guidelines or ask - Which suggests a lack of common sense above anything else.