Boston Terriers do bark but this isn't at the top of their "to do" list. Unlike other breeds that bark at the drop of a hat, the Boston Terrier has to be bored or pretty worked up about something to use their voice.
Yes, quite normal. Most dogs will not show quick interest in riding the skateboard. Put the dog on the skateboard and use a command like "Skate." When they stay on...
The Boston Terrier would be mid-table in a league of dogs that are easy or hard to train. These dogs have a lovely character but are sometimes too laid back...
It depends. An elevated Boston crab can't be too much more effective than the scorpion deathlock. If it does damage, it's enough to withstand long enough to reach the ropes...