Danger Zone

This is the hardest achievement in the game, however it's not that difficult since you only need 10 platinums out of 32 levels. Please be aware that this game is VERY random with the bounces and smashes, so you will most likely have to replay a mission multiple times before you get the result you want. I am posting my videos below mostly for an idea of when to explode and the path I took, so there's no way to exactly copy them. I found that some are a lot more difficult than others. I could consistently get close-ish to the platinum scores, but had to retry quite a few times sometimes to hit it. I'm sure these paths can be improved, but as this is the first post for this achievement, I'll leave it up unless something better comes along.

GENERAL TIPS
*There are 6 floating coins per level. 3 bronze, 2 silver, and 1 gold. If you collect all 3 bronzes, then both silvers, then the gold (in that order), you will get a Grand Slam bonus at the end which will earn you $5 million. If you collect them out of order (eg, bronze, silver, bronze, bronze, silver, gold), then you will earn a smash and grab bonus, which is worth $2.5 million. For most levels, the key to platinum is to get this Grand Slam bonus of $5 million and this is where my videos come in.
* You will get 1 smashbreaker after 4-10 crashes, and you can pick up extras mostly next to the coins. You press to activate it. You don't need all of these, but they help get to where you need to go. I often had 1 extra. The general idea of this is to explode when cars are around you for max score, or if not, then use it to get to where you need to go. NOTE: If you are still holding when you do your first smashbreaker, you will fly far into the air. If you are not, or holding brake , you will jump less. Different jumps suit different areas, so adjust accordingly (you should be able to tell in my video what I used by the height of the jump).
* Timing is everything. I try to time my videos so I smashed at the point that cars are crossing a path, so often you will see me use smashbreaker fast to get to a certain point. This is often me trying to get to a medal before traffic comes to me so I can smash and get to the next point (this is better for score).

I don't have videos for every level, but there are more than 10, so you should have enough to go by.

Test Phase 1-1: Up The Junction
Target Score: $12,000,000

Test Phase 1-2: Impact Protection
Target Score: $12,000,000

Test Phase 1-3: Hot Wired
Target Score: $16,000,000

Test Phase 1-4: No Need For Median
Target Score: $13,000,000

Test Phase 1-5: Burning Bridges
Target Score: $12,000,000

Test Phase 1-6: Freeway Entrance
Target Score: $16,000,000

Test Phase 1-7: Shock Treatment
Target Score: $21,000,000

Test Phase 1-8: Jump Start
Target Score: $21,000,000

Test Phase 2-1: Across The Line
Target Score: $14,000,000

Test Phase 2-2: Oncoming Traffic
Target Score: $16,000,000

Test Phase 2-3: Toll Violation
Target Score: $14,000,000

Test Phase 2-4: Tunnel Vision
Target Score: $16,000,000

Test Phase 2-5: Parallel Lines
Target Score: $17,000,000

Test Phase 2-6: Ahead Of The Curve
Target Score: $14,000,000

Test Phase 2-7: Brake Out
Target Score: $16,000,000

Test Phase 2-8: Tunnel of Shove
Target Score: $17,000,000

Test Phase 3-1: Narrow Margin
Target Score: $21,000,000

Test Phase 3-2: When Love and Freight Collide
Target Score: $16,000,000

Test Phase 3-3: Stop The Roundabouts
Target Score: $16,000,000

They get harder after this, so I stopped making videos. I would suggest if you are having trouble, just move on to the next one.

In addition to the excellent guide posted before me, I would like to throw in a tip or two for those who have not played the Burnout series...

You can "push" cars that are going in the same direction as you while still being able to handle your car after hitting them. What this allows you to do is cause a pileup in the vicinity while still maneuvering after the coins or another crash site.

In some levels you can actually just drive and pickup all the coins while doing this, because the wreckage you leave behind will get you points and then you can get a grand slam to go along with it.

Hope this helps someone in the future! I knew this existed in Burnout but didn't know these mechanics transferred over to this game until I was a couple of platinums away from the achievement. It made getting the last few much easier.