Since the down button is such important, why is there no alternate key for it?
Also, I would really love if the Computron Save message doesn't appear in the middle of the screen blocking half the view in the middle of a battle.
I think any level can be doable with a little patience after getting used to the controls as long as there is no moving enemies. Level 42 is not that hard, there is no moving enemies; on the other hand level 30 is diabolic because of the moving enemies.
@punkedshadow; This actually happens when you load a saved game. If you don't move your HQ after loading a saved game and keep bombing, you won't be able to move your truck. The way around this is either move your HQ immediately after loading a saved game or end the day when you can't move your truck.
If you go to the 'Build Town' area & look around the map, you can see where the next Gold marked area from the Surveyor's office will be. And then you can move your HQ to the appropriate place.
For those trying the hard badge: Along with tiri23's great comment, always remember that the score in Survival mode is based on how far you have gone rather than how many enemies killed. And most problematic enemies are the hooded guys & the bats because they shoot at you, the ogres will just pass along. So, kill the hooded guys & bats first, trying to avoid the ogres.
If anyone is having difficulty in reaching Mars within 20 days, you should know that only Height, Band, Fuel Tank, Radar & E-Rocket upgrades are enough to reach higher.. Others are pretty much useless. Also don't forget to get Radar as soon possible, its extremely useful..
Just for once, violence WAS the answer.