Yeah, the extra man thing happens when you finish a board and technically die at the same time. A flag is set thinking you died, but before the program run the death routine, the finishing the level takes priority and you move on. But, since the death flag was set, on the next baord it thinks you died before, so the beginning of the board shows one extra man. Because the game like for it to look like Mario came from up top to appear on the board at the bottom after a death.
Another minor glitch would be if you die on rivets level 5 or more, the "How high can you get" reverts back to 125m instead of 150m.
I'd like to see that Dean glitch, but looks like he didn't highlight it. There's a 3 hour plus gameplay on March 8th if someone wants to go find it and higlight it.