Good concept, game, bad (or not really good) implementation in terms of difficulty. (It's quite hard at the start; i'm naturally bad at these games :P)
If you have trouble with AS2, Newgrounds's flash forum has a whole section on AS2, based on forum thread posts. Search AS2 Main in the forum to find the main contents thread. Also try googling things, can be helpful if you know how to construct your query well.
The Lightspeed(?) level, the one before the block that doesn't change level, is bugged i think. The block only appeared once, and the screen's blocks didn't change when i moved the mouse. I had to rightclick -> forward to skip to the next level. You might also want to remove that. Loads of tuts on the internet to tell you how. Also, if you die, either by mine or anything else, you shouldn't have to restart the whole game. It puts people off replaying the game. Add a death counter, 'lives', or anything else.
Also although the engine of the game (coloured blocks moving through spectrums on trigger) is a good idea, just having the player search for a block for the next level isn't using the full capabilities and potential of the engine. Other than that, this game is a good first game! =D
I love the atmosphere. The calm music coupled with the serene and often surreal photos really makes the game one of a kind. I especially love the last scene with the rising sun.
SpearThrust, you can find out whether you need a preloader using the fake load function in the testing part of flash. I know it's in CS3. Should be easy to find and use. And instead of uploading it here, you can upload it on imageshack, thereby still testing preload without the complaints you have recieved on here.
GreatestSoloEver, how can it possibly be good for the start of a basic flash game? What start for what 'basic' flash game? You must have very low expectations.
Good game! Just too short and doesn't tell you what to press to get upgrades until a bit later in the game. Also might wanna tweak the prices for the bottom 3 upgrades.