These days, I played the original ROTT under Dosbox and decided to do a little challenge: trying to get the maximum amount of bonuses for every level in Crezzy mode to get a very high score. All that without cheating. For some levels, it's impossible to get the famous "Bonus Bonus" as there may be missing elements on the level preventing to do a specific bonus. For example, if there's no plants on the level, I can't get "Repulican Bonus 2".
If you're meticulous, you may notice something wrong going with a particular bonus...
No? You don't catch?

I'm talking here about the "Ground Zero Bonus". As I said earlier, I'm playing in Crezzy difficulty mode, not Easy one. And well, under that difficulty, a FireWall missile is deadly, even at full health, unless wearing an Asbestor armour. But some levels don't have such an armour, so how did I get that bonus on these levels without dying? No, I don't cheat! In fact, I'm using the exploit of a little glitch. I let you guess.
For now, I'm playing the Deluxe Shareware version of ROTT and here are the results so far. Next, I'm gonna play the Registered version. These screenshots have been taken from Dosbox and haven't been "Photoshoped" at all. I swear!
Here are the first 4 levels:
The HUNT Begins
Prelude to a Kill
Jumpin' Jehoshaphat
GADZOOKS!