The scores do not go down. The columns in the table show different things. The driver and programming which add together to form the Skills score used for the ranking has to happen at the same event. The “Highest Programming Skills” is just that; it might well be higher than the one used to calculate your high skills score, simply because it happened at a different event. And at that other event, your driver skills score was low enough that even when combined with your “Highest Programming Skills,” the total was less that at your record-setting event.
So, your score will never go down; you’re not penalized for inconsistent scores at later tournaments.
No, it’s not supposed to use the highest programming and driver. It uses the highest COMBINED programming and driver from a single tournament. The highest programming is shown and used as a tie breaker.
You should read what I said more carefully. It is not the latest competition. The two scores that are totaled to form the combined skills score are the ones from the competition where the total is highest. If that happened at the first competition you attended, then that’s the two scores that will be used.
Later, if you make a lower score, it won’t lower your overall score. If you make a higher score on programming but a lower score on driver at a later event, the higher programming score will replace the “Highest Programming Skills”. The total score will go up only if the combined score at that event is higher than your previous combined score at a single event.
[Edit: just saw @TriDragon’s post. He says it much more compactly than me.]