im sorry but this needs some work
though the game idea is great, the overall style and handling is a catastrophy.
Here is why i think that:
First the controls:
you have to click with the mouse and use the Arrow keys, but you need to change how your hands are constantly. Please make the contrls as following:
Instead of mouseclick: s, instead of space: Left mouse button
instead of right and left arrows: d and a and instead of up or down w and s
so you have the hands on wasd and your mouse. this makes gameplay much easier.
The style is ok, i would have liked more realistic boxes and overall cars etc, but i think this game is more for kids than adults.
The dynamics are terrible. The car accelerates too fast and the boxes are not heavy enough so they fly around like balloons.
Also why is the crane/forklift throwing the boxes around instead of really sorting them in? i would like more control over where i can set the boxes.
The music gets annoying very fast, for a game that needs so long for each level, i would prefer a track thats at least as long as one level, which you have, but the sound seems to stay the same, it even could be a loop. something more calm would be nicer.
so i hope i could help a little bit, the most annoying thing is the controls, you really need to fix that.