The keyboard issue is to do with which element on the screen has "focus". When you click on a link in the "Forum Latest" panel, that link gets focus and the Forum opens in another tab or window. When you return to the Chihuahua page, the forum link is still in focus, and so any letters you key in are ignored and the Enter key serves to open the forum link again. The reason why pressing a letter key doesn't return focus to the puzzle is probably related to the fact that the forum summary is actually a separate web page, inside an iframe. But as cmh explained, clicking somewhere in the game area should do the trick.
The order of players on the scoreboard has had a few glitches over the years, so it is possible it isn't always doing what it's intended to. But the way it should work is that where a group of players are on the same score, the players with a star will appear above those without a star. And if there are multiple stars available in the puzzle, those with the most stars will go highest. Then, within the group of players with the same score and the same number of stars, the time when the player reached that score will determine their place on the scoreboard - i.e. the player who reached that level first will be on top.
However, there is another factor when you are looking at a scoreboard which displays the hit rate. (For daily puzzles, this applies to the Challenge puzzle only, and only when the scoreboard option has been selected to include rare words in the counts. Some custom puzzles also show the hit rate.) In these cases the hit rate determines the order of players with the same score and number of stars, and time only comes into play where two players have the same score, star count and hit rate.
Another complication is that the scoreboard you can see isn't always right up to date, and the scores on the server are not always updated immediately a player plays a word, so the accuracy of the time sequence is not absolutely precise.
And finally, yes, yelnats, graphics without the white border would be great - the competition for these honours will become even fiercer!
