[Temporary_User]

I play pool casually at the pubs fairly often. The other day a couple friends and I were out playing. Since it was just the 3 of us playing, one of us would sit out and play the winner. A guy at the pub saw the 3 of us switching in and out, so he asked if we cared if he joined us inorder to make doubles. We agreed.
Now I only play at pubs, so I'm not too familiar with the specific rules (as if creating this thread wasn't obvious enough). I'm curious as to whether I have simply been misinformed about the rules throughout the years, or if this guy has been, or if he is correct but simply a rule nazi.

The first instance that I figured this guy was a rule nazi, was on my first shot. He broke and didn't sink anything. I shot my ball, and it went in the intended pocket. This guy calls out that my ball bumped one of the other balls (not necessarily his at this point) on the way in that was not my intended ball nor the same kind. No one else saw this, as no one else was really paying attention.
I don't know the rules on this, I thought since my intended ball went in, that it was all fair. Since I wasn't sure, I let his team take the next shot. He also stated that it should still open table.

The 2nd instance was off a scratch. I always played that you had to place the cue ball behind the 2nd triangle and had to hit it past the 3rd triangle from the other side (hopefully that makes sense). After a scratch, this guy set his ball up on the 2nd triangle, but simply shot the next closest ball into the side pocket. I asked him about that rule, and he stated that you only had to go forward with it. ???

The third was on a shot my friend had to take. We only had one ball left on the table (other than the 8-ball). This ball was completely blocked in by 2 of his balls and the railing. There wasn't really a chance my friend could hit our ball, but inorder to take a shot he decided to try. I know that if our ball had went in after hitting one of his balls first, we would have had to give up our next shot. However, none went in, and since the cue ball hit the other guys ball first, this guy stated that it was "ball in hand", and he proceeded to place the cue ball on the table to his liking and proceeded to hit another ball in (obviously an extremely easy shot since he basically put it right in front of it, a perfect location).

I always play simply for fun. Will only play for drinks if the other person suggests it. I would just simply like to know more of the rules in case I run across a fellow like this guy again, and that way I know.