If you're having to guess, you're doing it wrong. If you haven't found the "show incomplete" button, you need to look harder instead of complaining there isn't one. I've found the hint button a little hard to use, seems you have to have X selected to use it properly.
BatmanAoD, while I agree with you, those boxes clearly have more air resistance than our little friend. And I think they mean "Thx Newton" for 'discovering' gravity.
The only problem comes when you reach the limit of the number of inputs your keyboard can handle simultaneously. Well, that, and not being very good at multi-tasking. I'm gonna badger a friend into playing this with me.
The following mechanics are a pain, to get near the edge of the screen I have to be careful not to let my mouse go outside it. And of course this doesn't help me dodge quickly.
I just want to listen to the title screen music :>
Oh FatCatAttack, you're so lost. The majority of goods do not go by air, I'm pretty sure rail didn't decline because aeroplanes were invented. In a lot of countries rail is still going strong, and they aren't the ones with no internal flights either.
What have you done this time, you meddling milquetoast? Now Purple Tentacle is free to use his evil mutant powers to take over the world, and ENSLAVE ALL HUMANITY!
I wouldn't mind knowing what the achievements are, as I'm kinda a noob at this sort of game at best, and it's frustrating when I get led on by "die to X" achievements and then find there aren't more of them.
 "Pigs Can Fly"){kind=icon}
 "Picma Squared"){kind=icon}
 "Box Clever Level Pack"){kind=icon}
 "Splitter Pals"){kind=icon}
 "Multitask 2"){kind=icon}
 "Steelcurse"){kind=icon}
 "Front Runner"){kind=icon}
 "Piano Talent 1.2"){kind=icon}
 "Mamono Sweeper"){kind=icon}
 "Zilch"){kind=icon}
 "Run 2"){kind=icon}
 "The Legend of the Golden Robot"){kind=icon}
 "Choo Choo Puzzles"){kind=icon}
 "Tentacle Wars. The Purple Menace"){kind=icon}
 "Omega Box"){kind=icon}
 "Another Cave Runner"){kind=icon}
 "Sugar, sugar"){kind=icon}