@siasia, The error is from the loading of the sound effect file in the "res" folder. I'n not sure why it's happening, but my guess would be that either the files are not there or they are protected so that the program can't access them.
@Hume and derosa, Some great ideas right there! And, just to answer some of the questions:
The yellow sphere does not grow, it was my original idea, but I couldn't think of a good way to make implement it. Since there is not much of a surrounding environment the only way I can think of making the sphere move is o make it cover more of the screen, which would make it really hard to see.
The second counter is for the high score. There were some problems with it in my first upload, but now the high score should work fine and also be saved on your computer.