Move around with left and right, and chainsaw stuff with the space bar. Make your way to the other end of the floor to continue. Hint: Get right up against things before chainsawing them, and keep at it until you cut all the way trough.
Quality controls (press numbers at any time):
1= LOW QUALITY;
2= MEDIUM QUALITY;
3= HIGH QUALITY;
4= SMART QUALITY(low while moving, high while standing).
Press S to toggle background music