A couple of points I don't agree on.
Firstly, the score system appears to work like this: whatever score you had up till the boss fight is saved. You will always enter boss fight with 1000 score (I guess it is to give you a set HP since score acts as HP anyway). Whatever score you get for boss fight is added on (assuming you didn't die and restart the boss, I suppose) to that you got earlier.
So you don't actually have to enter boss fight with 1470 or anything like that.
Next, for the survival medal, I don't think it is a good idea to go K9 anywhere at all. I typically use it to get me past the minefield, emerging at about 6k+ score mark. However with only a single laser left, and fuel consumption increased, cars increased, and enemies shooting fireballs, I find it way too hard to upgrade my weapon and get enough shields to keep up with the fuel consumption even if I don't get hit at all. Triple laser hitting enemies will net you more shields, so it is probably a better idea to keep your fingers crossed and get through the minefield without K9.
I haven't gotten that medal yet myself, nor made it past 10k. Maybe there is a point near the end where you should just go K9 and it will make you invulnerable till 15k mark.
NikLink
I'm having trouble at the beginning of the game when the bridge comes up, since it's really tricky to judge where exactly the columns are. Any tips?
DiMono
Try to be between 1/4 - 1/3 of the way up from the bottom of the screen, that seems to be the safe spot. Beyond that, just practice, practice, practice!