To use some of the larger background music soundtracks, you will need to increase the memory allocated to Tetris Max by your Mac. In general, you will need to allocate roughly 650k plus the size of the music file in order to use a particular music file.
To change Tetris Max's memory allocation, click once on the Tetris Max icon in the finder to highlight it, then select "get info" from the file menu. From the info window that appears, edit the field labeled "preferred size" to set how much memory will be allocated to Tetris Max. When you're finished, close the info window, and you should be all set.
